Obligation Interstate Energy & Lighting 2.3% ( US461070AS31 ) en USD

Interstate Energy & Lighting

100 % ▼

Etas-Unis

US461070AS31 ( en USD )

2.3% par an ( paiement semestriel )

01/06/2030

Prospectus brochure de l'obligation Interstate Power and Light US461070AS31 en USD 2.3%, échéance 01/06/2030

1 000 USD

400 000 000 USD

461070AS3

A- ( Qualité moyenne supérieure )

Baa1 ( Qualité moyenne inférieure )

01/12/2025 ( Dans 115 jours )

Interstate Power and Light (IPL) était une entreprise d'électricité américaine, rachetée par Alliant Energy en 2000.

L'Obligation émise par Interstate Energy & Lighting ( Etas-Unis ) , en USD, avec le code ISIN US461070AS31, paye un coupon de 2.3% par an.
Le paiement des coupons est semestriel et la maturité de l'Obligation est le 01/06/2030

L'Obligation émise par Interstate Energy & Lighting ( Etas-Unis ) , en USD, avec le code ISIN US461070AS31, a été notée Baa1 ( Qualité moyenne inférieure ) par l'agence de notation Moody's.

L'Obligation émise par Interstate Energy & Lighting ( Etas-Unis ) , en USD, avec le code ISIN US461070AS31, a été notée A- ( Qualité moyenne supérieure ) par l'agence de notation Standard & Poor's ( S&P ).

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Table of Contents
CALCULATION OF REGISTRATION FEE

Maximum
Title of each class of
aggregate
Amount of
securities to be registered

offering price

registration fee (1)
2.300% Senior Debentures due 2030

$398,300,000

$51,700

(1)
The filing fee is calculated in accordance with Rule 457(r) under the Securities Act of 1933.
Table of Contents
Filed Pursuant to Rule 424(b)(5)
Registration No. 333-222076-02

Prospectus Supplement
(To Prospectus dated December 15, 2017)
$400,000,000
Interstate Power and Light Company
2.300% Senior Debentures due 2030
We will pay interest on the senior debentures semi-annually in arrears on June 1 and December 1 of each year, beginning on December 1, 2020. The
senior debentures will mature on June 1, 2030. We may redeem some or all of the senior debentures at our option at any time or from time to time prior to
March 1, 2030 (3 months prior to their maturity), at the applicable redemption price described in this prospectus supplement plus accrued and unpaid
interest, if any, to, but excluding the redemption date. We may also redeem some or all of the senior debentures from time to time on or after March 1,
2030 (3 months prior to their maturity), at a redemption price equal to 100% of the principal amount of the senior debentures to be redeemed, plus accrued
and unpaid interest, if any, to, but excluding, the redemption date.
The senior debentures will be our unsecured senior obligations and rank equally with our other unsecured senior indebtedness from time to time
outstanding. The senior debentures will be issued only in registered form in minimum denominations of $2,000 and integral multiples of $1,000 in excess
thereof. The senior debentures are a new issue of securities with no established trading market. We currently have no intention to apply to list the senior
debentures on any securities exchange or to seek their admission to trading on any automated quotation system.
Investing in the senior debentures involves risks. See "Risk Factors" beginning on page S-5 of this prospectus supplement, page 4 of the
accompanying prospectus, page 32 of our Quarterly Report on Form 10-Q for the quarter ended March 31, 2020 and page 13 of our Annual
Report on Form 10-K for the year ended December 31, 2019, as such discussion may be amended or updated in other reports filed by us with the
U.S. Securities and Exchange Commission, or the SEC. The Risk Factors included in our Quarterly Report on Form 10-Q and our Annual Report
on Form 10-K, as amended or updated, are incorporated by reference herein.

Per Senior

Debenture

Total

Public offering price (1)

99.575%
$398,300,000
Underwriting discount

0.650%
$
2,600,000
Proceeds, before expenses, to Interstate Power and Light Company (1)

98.925%
$395,700,000

(1)
Plus accrued interest, if any, from June 2, 2020, if settlement occurs after that date.
Neither the SEC nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or
the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
The senior debentures will be available for delivery in book-entry form only through The Depository Trust Company, or DTC, on or about June 2,
2020.

Joint Book-Running Managers
Goldman Sachs & Co. LLC

Mizuho Securities

MUFG

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Co-Managers
Comerica Securities

Ramirez & Co., Inc.

TD Securities

The date of this prospectus supplement is May 26, 2020.
Table of Contents
TABLE OF CONTENTS

Prospectus Supplement

Page
About this Prospectus Supplement
S-ii
Forward -Looking Statements
S-iii
Prospectus Supplement Summary
S-1
Risk Factors
S-5
Use of Proceeds
S-6
Capitalization
S-7
The Company
S-8
Description of Senior Debentures
S-9
Underwriting
S-14
Legal Matters
S-20
Experts
S-20
Prospectus

Page
About this Prospectus

1
Forward -Looking Statements

2
Interstate Power and Light Company

3
Risk Factors

4
Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements

5
Use of Proceeds

5
Description of Preferred Stock

6
Description of Debt Securities

8
Plan of Distribution

16
Where You Can Find More Information

18
Legal Matters

20
Experts

20

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Table of Contents
ABOUT THIS PROSPECTUS SUPPLEMENT
This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering. The second part, the
accompanying prospectus, gives more general information, some of which may not apply to this offering. You should read this entire prospectus
supplement, as well as the accompanying prospectus and the documents incorporated by reference that are described under "Where You Can Find More
Information" in the accompanying prospectus. Some of these documents, however, are filed on a combined basis with our parent, Alliant Energy
Corporation, and its direct subsidiary, Wisconsin Power and Light Company. Information contained in these documents relating solely to those entities is
filed by them on their own behalf and not by us and is not incorporated by reference in this prospectus supplement or the accompanying prospectus. The
senior debentures are not obligations of, or guaranteed by, Alliant Energy Corporation or Wisconsin Power and Light Company and you should not rely on
that information when deciding whether to invest in our senior debentures. In the event that the description of the offering varies between this prospectus
supplement and the accompanying prospectus, you should rely on the information contained in this prospectus supplement.
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You should rely only on the information relating solely to Interstate Power and Light Company contained or incorporated by reference in this
prospectus supplement, the accompanying prospectus and any related free writing prospectus prepared by or on behalf of us or to which we have referred
you. We have not, and the underwriters have not, authorized any other person to provide you with different information. If anyone provides you with
different or inconsistent information, you should not rely on it. We are not, and the underwriters are not, making an offer to sell these securities in any
jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying
prospectus and the documents incorporated by reference is accurate only as of the respective dates of those documents in which the information is
contained. Our business, financial condition, results of operations and prospects may have changed since any such date.
Unless we otherwise indicate or unless the context requires otherwise, all references in this prospectus supplement to "we," "our," "us" or similar
references mean Interstate Power and Light Company.
Our principal executive offices are located at Alliant Energy Tower, 200 First Street, SE, Cedar Rapids, Iowa 52401, and our telephone number is
(319) 786-4411.

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FORWARD-LOOKING STATEMENTS
This prospectus supplement, the accompanying prospectus and the information incorporated by reference herein or therein contain forward-looking
statements intended to qualify for the safe harbors from liability established by the Private Securities Litigation Reform Act of 1995. All statements, other
than statements of historical fact, included in this prospectus supplement or in the accompanying prospectus or incorporated by reference herein or therein,
including statements regarding anticipated financial performance, business strategy and management's plans and objectives for future operations, are
forward-looking statements. These forward-looking statements can be identified as such because the statements generally include words such as "may,"
"believe," "expect," "anticipate," "plan," "project," "will," "projections," "estimate," or other similar expressions. These forward-looking statements are
subject to certain risks and uncertainties that could cause actual results to differ materially from those expressed in, or implied by, these statements.
Readers are cautioned not to place undue reliance on these forward-looking statements. All forward-looking statements included in this prospectus
supplement, the accompanying prospectus or in any document incorporated by reference herein or therein speak only as of the date of this prospectus
supplement, the accompanying prospectus or the document incorporated by reference, as the case may be. Additional information concerning factors that
could cause actual results to differ materially from those in the forward-looking statements is contained under "Risk Factors" on page S-5 of this
prospectus supplement, page 4 of the accompanying prospectus and in other documents that we file from time to time with the SEC that are incorporated
by reference into this prospectus supplement and the accompanying prospectus, including, but not limited to, the risk factor disclosure beginning on page 32
of our Quarterly Report on Form 10-Q for the quarter ended March 31, 2020 and page 13 of our Annual Report on Form 10-K for the year ended
December 31, 2019. Some, but not all, of the risks and uncertainties that could materially affect actual results include the following:

·
our ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of and/or the return on costs, including fuel
costs, operating costs, transmission costs, deferred expenditures, deferred tax assets, tax expense, capital expenditures, and remaining costs

related to electric generating units that may be permanently closed and certain other retired assets, decreases in sales volumes, earning our
authorized rates of return, and the payments to our parent, Alliant Energy Corporation, of expected levels of dividends;

·
federal and state regulatory or governmental actions, including the impact of legislation, and regulatory agency orders;

·
the direct or indirect effects resulting from the novel coronavirus (COVID-19) pandemic on sales volumes, margins, operations, employees,
contractors, vendors, the ability to complete construction projects, supply chains, customers' inability to pay bills, suspension of disconnects

and waiving of late fees applied to past due accounts, the market value of the assets that fund pension plans and the potential for additional
funding requirements, the ability of counterparties to meet their obligations, compliance with regulatory requirements, the ability to
implement regulatory plans, economic conditions and access to capital markets;

·
the impact of customer- and third party-owned generation, including alternative electric suppliers, in our service territory on system

reliability, operating expenses and customers' demand for electricity;

·
the impact of energy efficiency, franchise retention and customer disconnects on sales volumes and margins;

·
the impact that price changes may have on our customers' demand for electric, gas and steam services and their ability to pay their bills;

·
the ability to utilize tax credits and net operating losses generated to date, and those that may be generated in the future, before they expire;

·
the direct or indirect effects resulting from terrorist incidents, including physical attacks and cyber-attacks, or responses to such incidents;

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·
the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable

information, including associated costs to notify affected persons and to mitigate their information security concerns;

·
any material post-closing payments related to any past asset divestitures which could result from, among other things, indemnification

agreements, warranties or litigation;

·
employee workforce factors, including changes in key executives, ability to hire and retain employees with specialized skills, ability to create

desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;

·
weather effects on results of utility operations;

·
issues associated with environmental remediation and environmental compliance, including compliance with all environmental and emissions
permits, the coal combustion residuals rule, future changes in environmental laws and regulations, including federal, state or local regulations

for carbon dioxide emissions reductions from new and existing fossil-fueled electric generating units, and litigation associated with
environmental requirements;

·
increased pressure from customers, investors and other stakeholders to more rapidly reduce carbon dioxide emissions;

·
the ability to defend against environmental claims brought by state and federal agencies, such as the U.S. Environmental Protection Agency,

state natural resources agencies or third parties, such as the Sierra Club, and the impact on operating expenses of defending and resolving such
claims;

·
continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;

·
inflation and interest rates;

·
the ability to complete construction of wind and solar projects within the cost caps set by regulators and to meet all requirements to qualify

for the full level of production tax credits and investment tax credits, respectively;

·
changes in the price of delivered natural gas, purchased electricity and coal due to shifts in supply and demand caused by market conditions

and regulations;

·
disruptions in the supply and delivery of natural gas, purchased electricity and coal;

·
the direct or indirect effects resulting from breakdown or failure of equipment in the operation of electric and gas distribution systems, such as

mechanical problems and explosions or fires, and compliance with electric and gas transmission and distribution safety regulations, including
regulations promulgated by the Pipeline and Hazardous Materials Safety Administration;

·
issues related to the availability and operations of electric generating units, including start-up risks, breakdown or failure of equipment,

performance below expected or contracted levels of output or efficiency, operator error, employee safety, transmission constraints,
compliance with mandatory reliability standards and risks related to recovery of resulting incremental costs through rates;

·
impacts that excessive heat, storms or natural disasters may have on our operations and recovery of costs associated with restoration

activities;

·
changes to costs of providing benefits and related funding requirements of pension and other postretirement benefits plans due to the market

value of the assets that fund the plans, economic conditions, financial market performance, interest rates, life expectancies and demographics;

·
material changes in employee-related benefit and compensation costs;

·
changes in technology that alter the channels through which customers buy or utilize our products and services;

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·
impacts of our future tax benefits from Iowa rate-making practices, including deductions for repairs expenditures, allocation of mixed service

costs and state depreciation, and recoverability of the associated regulatory assets from customers, when the differences reverse in future
periods;

·
the impacts of adjustments made to deferred tax assets and liabilities from changes in the tax rates;

·
changes to the creditworthiness of counterparties with which we have contractual arrangements, including participants in the energy markets

and fuel suppliers and transporters;

·
current or future litigation, regulatory investigations, proceedings or inquiries;

·
reputational damage from negative publicity, protests, fines, penalties and other negative consequences resulting in regulatory and/or legal

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actions;

·
the effect of accounting standards issued periodically by standard-setting bodies;

·
the ability to successfully complete tax audits and changes in tax accounting methods with no material impact on earnings and cash flows;

and

·
other factors listed in Management's Discussion and Analysis of Financial Condition and Results of Operations in the combined Quarterly

Report on Form 10-Q and Annual Report on Form 10-K filed by Alliant Energy Corporation, Wisconsin Power and Light Company and us
for the quarter ended March 31, 2020 and the year ended December 31, 2019, respectively.
We assume no obligation, and disclaim any duty, to update the forward-looking statements in this prospectus supplement, the accompanying
prospectus or in any document incorporated by reference herein or therein, whether as a result of new information, future events or otherwise, except as
required by law.

S-v
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PROSPECTUS SUPPLEMENT SUMMARY
This summary highlights information contained in or incorporated by reference to this prospectus supplement and the accompanying
prospectus. This summary may not contain all of the information that may be important to you. You should read this entire prospectus supplement, as
well as the accompanying prospectus and the documents incorporated by reference to this prospectus supplement and the accompanying prospectus,
carefully before making a decision to invest in our senior debentures.
Our Company
We are a public utility primarily serving customers in Iowa. We are engaged principally in:

·
the generation and distribution of electricity to retail customers in select markets in Iowa;

·
the distribution and transportation of natural gas to retail customers in select markets in Iowa;

·
the sale of electricity to wholesale customers in Minnesota, Illinois and Iowa; and

·
the generation and distribution of steam for two customers in Cedar Rapids, Iowa.
We provide utility services to incorporated communities as directed by the Iowa Utilities Board, or IUB, and utilize non-exclusive franchises,
which cover the use of public right-of-ways for utility facilities in incorporated communities for a maximum term of 25 years. As of December 31,
2019, we served approximately 490,000 retail electric customers and 225,000 retail natural gas customers.
All of our common stock is owned by Alliant Energy Corporation, a regulated investor-owned public utility holding company with subsidiaries,
including us, serving primarily electric and natural gas customers in the Midwest. In 2019, 2018, and 2017, we had no single customer for which
electric, gas, steam and/or other sales accounted for 10% or more of our consolidated revenues.
We are subject to the jurisdiction of the IUB. We are also subject to the jurisdiction of the Federal Energy Regulatory Commission, or FERC.
Our parent corporation, Alliant Energy Corporation, is a "holding company" and we are a "subsidiary company" within the Alliant Energy
Corporation "holding company system" as defined under the Public Utility Holding Company Act of 2005, or PUHCA. As a result, we are subject to
some of the regulatory provisions of the PUHCA.

S-1
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The Offering
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The following is a brief summary of some of the terms of this offering. For a more complete description of the terms of the senior debentures,
see "Description of Senior Debentures" in this prospectus supplement and "Description of Debt Securities" in the accompanying prospectus.

Issuer
Interstate Power and Light Company
Senior debentures offered
$400 million aggregate principal amount of 2.300% senior debentures due 2030.
Maturity
June 1, 2030.
Interest payment dates
June 1 and December 1 of each year, beginning on December 1, 2020.
Ranking
The senior debentures will be our unsecured senior obligations and rank equally with our other
unsecured senior indebtedness from time to time outstanding. The senior debentures will also be
subordinated to any secured indebtedness to the extent of the assets securing such indebtedness.
We do not currently have any secured indebtedness.
Optional redemption
The senior debentures will be redeemable, at our option, in whole or in part at any time or from
time to time prior to March 1, 2030 (3 months prior to their maturity), at the applicable redemption
price described in "Description of Senior Debentures--Optional Redemption" plus accrued and
unpaid interest, if any, to, but excluding, the redemption date. We may also redeem all or a portion
of the senior debentures at our option at any time on or after March 1, 2030 (3 months prior to their
maturity), at a redemption price equal to 100% of the principal amount of the senior debentures to
be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date.
Covenants
The indenture governing the senior debentures contains covenants that, among other things, limit
our ability to:

· ?create certain types of secured indebtedness without providing for the senior debentures to be
equally and ratably secured; and

· ?consolidate, merge or sell assets.
These covenants are subject to important exceptions and qualifications, which are described under
the heading "Description of Debt Securities" in the accompanying prospectus.
No limitation on debt
The indenture governing the senior debentures does not limit the amount of senior unsecured debt
securities that we may issue or provide holders any protections should we be involved in a highly
leveraged transaction.

S-2
Table of Contents
Use of proceeds
We expect to receive net proceeds from this offering of approximately $395.0 million, after
deducting the underwriting discount and estimated offering expenses payable by us. We intend to
use the net proceeds from this offering to retire our $200 million aggregate principal amount of
3.65% senior debentures maturing on September 1, 2020 at or prior to maturity and for general
corporate purposes, as described under "Use of Proceeds."
Denominations
The senior debentures will be issued in minimum denominations of $2,000 and integral multiples
of $1,000 in excess thereof.
Risk factors
You should read "Risk Factors" on page S-5 of this prospectus supplement, on page 4 of the
accompanying prospectus and in the documents incorporated by reference herein for a discussion
of certain risks that prospective investors should consider before investing in the senior debentures.

S-3
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Table of Contents
Summary Consolidated Financial Information
The summary consolidated financial information below was selected or derived from our consolidated financial statements. The unaudited
interim period financial information, in our opinion, includes all adjustments, which are normal and recurring in nature, necessary for a fair
presentation for the periods shown. Results for the three months ended March 31, 2020 are not necessarily indicative of results to be expected for the
full fiscal year. The information set forth below is qualified in its entirety by and should be read in conjunction with our Management's Discussion
and Analysis of Financial Condition and Results of Operations and our consolidated financial statements and related notes incorporated by reference
into this prospectus supplement and the accompanying prospectus from our Quarterly Report on Form 10-Q for the quarterly period ended March 31,
2020 and our Annual Report on Form 10-K for the fiscal year ended December 31, 2019. See "Where You Can Find More Information" in the
accompanying prospectus.

Three Months Ended

Year Ended December 31,

March 31,

2017

2018

2019

2019

2020

(In millions)

Income Statement Data:

Revenues
$1,870.3 $2,042.3 $2,089.6 $ 555.1 $ 518.9
Operating income

304.1
350.8
402.8
73.5
96.7
Net income

227.0
274.2
294.3
55.9
85.2
Net income available for common stock

216.8
264.0
284.1
53.3
82.6

As of December 31,

As of March 31,

2018

2019

2020

(In millions)

Balance Sheet Data:

Current assets

$ 371.8
$ 409.4
$
435.6
Property, plant and equipment, net

6,781.5
7,480.7

7,589.4
Other non-current assets

1,258.1
1,387.4

1,379.1
Current liabilities

607.1

830.5

835.1
Long-term debt, net (excluding current portion)

2,552.3
2,947.3

2,947.9
Other non-current liabilities

2,021.3
2,027.9

2,025.7

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Table of Contents
RISK FACTORS
Investing in the senior debentures involves risk. You should carefully consider the following risk factors together with all the other information
contained in this prospectus supplement or the accompanying prospectus or incorporated by reference in this prospectus supplement or the accompanying
prospectus. You should also consider the risks and uncertainties discussed under the caption "Risk Factors" included in our Quarterly Report on Form 10-Q
for the quarter ended March 31, 2020 and our Annual Report on Form 10-K for the year ended December 31, 2019, which are incorporated by reference in
this prospectus supplement and the accompanying prospectus, and which may be amended, supplemented or superseded from time to time by other reports
we file with the SEC in the future.
Absence of market for the senior debentures--The senior debentures are a new issue of securities with no established trading market. We
currently have no intention to apply to list the senior debentures on any securities exchange or to seek their admission to trading on any automated
quotation system. Accordingly, we cannot provide any assurance as to the development or liquidity of any market for the senior debentures. See
"Underwriting." Furthermore, the market price for the senior debentures may be adversely impacted by fluctuations in interest rates.

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Table of Contents
USE OF PROCEEDS
We expect to receive net proceeds from this offering of approximately $395.0 million, after deducting the underwriting discount and estimated
offering expenses payable by us. We intend to use the net proceeds from this offering to retire our $200 million aggregate principal amount of 3.65% senior
debentures maturing on September 1, 2020 at or prior to maturity and for general corporate purposes. Pending application of the proceeds from this
offering, we intend to place the proceeds in short-term instruments.

S-6
Table of Contents
CAPITALIZATION
The following table sets forth our consolidated capitalization as of March 31, 2020 on an actual basis and as adjusted to give effect to this offering
and the anticipated use of the net proceeds from this offering as described under "Use of Proceeds."

As of March 31, 2020

% of Total

Actual
As Adjusted
as Adjusted

(In millions)

Common equity:

Common stock

$
33.4
$
33.4

0.5%
Additional paid-in capital

2,447.8

2,447.8

35.2
Retained earnings

914.2

914.2

13.2

Total common equity

3,395.4

3,395.4

48.9
Cumulative preferred stock

200.0

200.0

2.9
Long-term debt, net (excluding current portion):

Existing long-term debt (excluding current portion)

2,947.9

2,947.9

42.4
Senior debentures offered hereby

--

400.0

5.8

Total long-term debt, net (excluding current portion)

2,947.9

3,347.9

48.2

Short-term debt (including current maturities of long-term debt)(1)

200.0

--

0.0

Total capitalization(1)

$6,743.3
$
6,943.3

100.0%

(1)
Includes $200.0 million 3.65% senior debentures that will mature in September 2020.

S-7
Table of Contents
THE COMPANY
We are a public utility primarily serving customers in Iowa. We are engaged principally in:

·
the generation and distribution of electricity to retail customers in select markets in Iowa;

·
the distribution and transportation of natural gas to retail customers in select markets in Iowa;

·
the sale of electricity to wholesale customers in Minnesota, Illinois and Iowa; and

·
the generation and distribution of steam for two customers in Cedar Rapids, Iowa.
We provide utility services to incorporated communities as directed by the IUB and utilize non-exclusive franchises, which cover the use of public
right-of-ways for utility facilities in incorporated communities for a maximum term of 25 years. As of December 31, 2019, we served approximately
490,000 retail electric customers and 225,000 retail natural gas customers.
All of our common stock is owned by Alliant Energy Corporation, a regulated investor-owned public utility holding company with subsidiaries,
including us, serving primarily electric and natural gas customers in the Midwest. In 2019, 2018, and 2017, we had no single customer for which electric,
gas, steam and/or other sales accounted for 10% or more of our consolidated revenues.
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We are subject to the jurisdiction of the IUB. We are also subject to the jurisdiction of FERC. Our parent corporation, Alliant Energy Corporation, is
a "holding company" and we are a "subsidiary company" within the Alliant Energy Corporation "holding company system" as defined under the PUHCA.
As a result, we are subject to some of the regulatory provisions of the PUHCA.

S-8
Table of Contents
DESCRIPTION OF SENIOR DEBENTURES
We have summarized provisions of the senior debentures below. This summary supplements and, to the extent inconsistent with, replaces the
description of the general terms and provisions of the debt securities under the caption "Description of Debt Securities" in the accompanying prospectus.
We will issue the senior debentures as a separate series of securities under an indenture, dated as of August 20, 2003, between us and The Bank of New
York Mellon Trust Company, N.A., as successor trustee, and an officer's certificate with respect to the senior debentures. The indenture is described in the
accompanying prospectus.
General
The indenture does not limit the aggregate principal amount of senior unsecured debt securities that we may issue under it, and provides that we may
issue, without the consent of holders of the senior debentures, securities under the indenture from time to time in one or more series pursuant to the terms
of one or more supplemental indentures, board resolutions or officer's certificates creating the series. The indenture does not give holders of the senior
debentures protection in the event we engage in a highly leveraged or other transaction that may adversely affect holders of the senior debentures. As of the
date of this prospectus supplement, we have $200.0 million aggregate principal amount of 3.65% senior debentures due September 2020, $500.0 million
aggregate principal amount of 3.25% senior debentures due 2024, $50.0 million aggregate principal amount of 5.50% senior debentures due 2025,
$250.0 million aggregate principal amount of 3.40% senior debentures due 2025, $500.0 million aggregate principal amount of 4.10% senior debentures
due 2028, $300.0 million aggregate principal amount of 3.60% senior debentures due 2029, $100.0 million aggregate principal amount of 6.45% senior
debentures due 2033, $125.0 million aggregate principal amount of 6.30% senior debentures due 2034, $300.0 million aggregate principal amount of 6.25%
senior debentures due 2039, $250.0 million aggregate principal amount of 4.70% senior debentures due 2043, $300.0 million aggregate principal amount of
3.70% senior debentures due 2046 and $300.0 million aggregate principal amount of 3.50% senior debentures due 2049 outstanding under the indenture.
We are initially offering the senior debentures in the aggregate principal amount of $ million. We may, without the consent of the holders of the
senior debentures, issue additional senior debentures in the future having the same ranking, interest rate, maturity and other terms, except for the public
offering price, issue date and, if applicable, the initial interest payment date as the senior debentures we offer by this prospectus supplement. Any such
additional senior debentures having such similar terms, together with the senior debentures, may constitute a single series of senior debentures under the
indenture.
No sinking fund will be established for the benefit of the senior debentures.
The transferor of any senior debenture shall provide or cause to be provided to the trustee all information necessary to allow the trustee to comply
with any applicable tax reporting obligations, including without limitation any cost basis reporting obligations under Internal Revenue Code Section 6045.
The trustee may rely on information provided to it and shall have no responsibility to verify or ensure the accuracy of such information.
Maturity and Interest
The senior debentures will mature on June 1, 2030. Each senior debenture will bear interest from June 2, 2020, or from and including the most recent
interest payment date to which we have paid interest, at the rate of 2.300% per year. We will pay interest semi-annually in arrears, on June 1 and
December 1, commencing December 1, 2020, to the persons in whose names the senior debentures are registered at the close of business on the fifteenth
calendar day (whether or not a business day) before each interest payment date. Interest will be computed on the basis of a 360-day year comprised of
twelve 30-day months. In the event that any interest payment date, redemption date or the maturity date does not fall on a business day, payment on the
senior debentures will be made on the immediately succeeding business day, without any additional interest paid as a result of such delay.

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Ranking
The senior debentures will be our senior, unsecured and unsubordinated obligations, ranking equally and ratably with all our other senior, unsecured
and unsubordinated obligations from time to time outstanding. The senior debentures will be effectively subordinated to all of our secured indebtedness to
the extent of the assets securing such indebtedness. We do not currently have any secured indebtedness.
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As of March 31, 2020, giving pro forma effect to this offering and our expected use of the net proceeds of the offering, we would have had $3,347.9
million aggregate principal amount of unsecured long-term debt outstanding (excluding current portion).
Optional Redemption
At any time or from time to time prior to March 1, 2030 (3 months prior to their maturity), or the Par Call Date, the senior debentures will be
redeemable as a whole or in part, at our option, at a redemption price equal to the greater of (i) 100% of the principal amount of such senior debentures and
(ii) the sum, as determined by the Independent Investment Banker and delivered to the trustee, of the present values of the remaining scheduled payments of
principal and interest thereon that would be due if the senior debentures matured on the Par Call Date (exclusive of interest accrued to the date of
redemption) discounted to the redemption date on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate
plus 25 basis points, plus in each case accrued and unpaid interest, if any, to, but excluding, the date of redemption.
At any time on or after the Par Call Date, the senior debentures will be redeemable as a whole or in part, at our option, at a redemption price equal to
100% of the principal amount of the senior debentures to be redeemed plus accrued and unpaid interest, if any, to, but excluding, the redemption date.
"Comparable Treasury Issue" means the United States Treasury security or securities selected by an Independent Investment Banker as having an
actual or interpolated maturity comparable to the remaining term of the senior debentures (assuming for this purpose that the senior debentures matured on
the applicable Par Call Date) to be redeemed that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing
new issues of corporate debt securities of a comparable maturity to the remaining term of such senior debentures.
"Comparable Treasury Price" means, with respect to any redemption date, (A) the average of the Reference Treasury Dealer Quotations for such
redemption date, after excluding the highest and lowest such Reference Treasury Dealer Quotations, or (B) if the Independent Investment Banker obtains
fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.
"Independent Investment Banker" means one of the Reference Treasury Dealers appointed by us.
"Reference Treasury Dealer" means (i) Goldman Sachs & Co. LLC and its successors (or a primary U.S. Government securities dealer located in the
United States (a "Primary Treasury Dealer") selected by Goldman Sachs & Co. LLC or one of its affiliates), (ii) Mizuho Securities USA LLC and its
successors (or a Primary Treasury Dealer selected by Mizuho Securities USA LLC or one of its affiliates), (iii) MUFG Securities Americas Inc. and its
successors (or a Primary Treasury Dealer selected by MUFG Securities Americas Inc. or one of its affiliates), and (iv) one Primary Treasury Dealer selected
by the Company, and such Primary Treasury Dealers' respective successors; provided, however, that if any of the foregoing or their affiliates shall cease to
be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer.
"Reference Treasury Dealer Quotations" means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined
by the Independent Investment Banker, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its
principal amount) quoted in writing to the Independent Investment Banker by the Reference Treasury Dealers at 3:30 p.m. New York time on the third
business day preceding such redemption date.

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"Treasury Rate" means, with respect to any redemption date, the rate per annum equal to the semiannual equivalent yield to maturity or interpolated
(on a day count basis) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal
amount) equal to the Comparable Treasury Price for such redemption date.
Notice of any redemption will be mailed or sent electronically pursuant to applicable DTC procedures at least 30 days but not more than 60 days
before the redemption date to each holder of senior debentures to be redeemed. If less than all of the senior debentures are to be redeemed, and the senior
debentures are global securities, the senior debentures to be redeemed will be selected by DTC in accordance with applicable DTC procedures. If the senior
debentures to be redeemed are not global securities then held by DTC, the senior debentures to be redeemed will be selected by the trustee pursuant to the
indenture.
Unless we default in payment of the redemption price, on and after the redemption date interest will cease to accrue on the senior debentures or
portions thereof called for redemption.
The Trustee
The Bank of New York Mellon Trust Company, N.A., will act as trustee, registrar, transfer agent and paying agent for the senior debentures. We can
remove the trustee with or without cause upon six months' notice, and appoint a successor trustee, so long as no event which is, or after notice or lapse of
time would become, an event of default shall have occurred and be continuing during the six month period.
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