Prospectus Supplement No. 18 Filed Pursuant to Rule 424(b)(3)
(To Prospectus Dated November 2, 1999) Registration No. 333-89345
Prospectus Supplement
Dated January 12, 2000
This prospectus relates to the resale by the holders of our:
o $300,000,000 principal amount of 6.25% convertible notes due 2009,
o $425,500,000 principal amount of 2.25% convertible notes due 2009,
and
o the shares of Class A common stock issuable upon conversion of the
notes.
This prospectus supplement should be read in conjunction with, and may not be
delivered or utilized without, the prospectus dated November 2, 1999, including
any amendments or supplements thereto. The terms of the notes are set forth in
the prospectus.
The information in the table appearing under the heading "Selling
Securityholders" on page 42 in the prospectus is hereby amended by adding the
information below with respect to selling securityholders not previously listed
in the prospectus or in any amendments or supplements thereto, and by
superceding the information with respect to selling securityholders previously
listed in the prospectus or in any amendments or supplements thereto that are
listed below:
<TABLE>
<CAPTION>
Number of Shares Percentage of
Principal Amount of Class A Common Number of Class A
at Maturity of 2.25% Stock Issuable Shares of Class Common Stock
Notes Beneficially Upon Conversion of A Common Stock Outstanding as
Owned That May the 2.25% Notes That Beneficially of January
Selling Securityholders be Sold May be Sold Owned** 11, 2001***
----------------------- ------------------- ------------------- --------------- --------------
<S> <C> <C> <C> <C>
Goldman, Sachs & Co. (1) $1,000,000 41,666 -- *
<FN>
* Less than 1%.
** In addition to the shares issuable upon conversion of the notes.
*** Includes shares issuable upon conversion of the notes and additional shares
beneficially owned as of January 11, 2001.
(1) Entity shown in the table, or an affiliate of the entity, was one of the
initial purchasers of these notes and/or other notes of the Company that were
sold in a private placement. The initial purchasers acquired such notes at a
discount. In addition, some of these entities or their affiliates have
participated in other offerings of securities by the Company and/or have
performed other banking services for which they have received fees.
</FN>
</TABLE>
