Registration No. 333-31252
Rule 424(b)(3)
Supplement to Prospectus Supplement Dated February 24, 1999
Structured Asset Securities Corporation,
Mortgage Pass-Through Certificates, Series 1999-ALS1
Aurora Loan Services Inc.,
Master Servicer
On February 26, 1999, Structured Asset Securities Corporation
Mortgage Pass-Through Certificates, Series 1999-ALS1, Class 1-A, 1-AP, 2-A,
2-AP, 2-AX, 3-A, 3-AP, 3-AX, B1, B2, B3 and R (the "Offered Certificates")
were issued in an approximate original aggregate principal amount of
$284,147,098. The Offered Certificates represented beneficial interests in a
trust fund consisting primarily of three pools of fixed rate, conventional,
first lien residential mortgage loans (the "Mortgage Loans"). The Mortgage
Loans were deposited by Structured Asset Securities Corporation into the trust
fund for the benefit of certificateholders pursuant to a trust agreement by
and among Structured Asset Securities Corporation, as depositor, Aurora Loan
Services Inc., as master servicer, and The Chase Manhattan Bank, as trustee.
Lehman Brothers Inc., the underwriter, is an affiliate of the depositor and of
Aurora Loan Services Inc., the master servicer.
This supplement to the above-referenced Prospectus Supplement and the
related prospectus dated January 15, 1999 (together, the "Prospectus")
supplements and updates certain of the information set forth in the
Prospectus. Capitalized terms not defined herein have the meanings ascribed to
them in the Prospectus.
Underwriter:
LEHMAN BROTHERS
March 31, 2000
The table set forth under the heading "The Master Servicer" on page
S-51 of the Prospectus Supplement is hereby updated, in its entirety, as
follows:
<TABLE>
<CAPTION>
Delinquencies and Foreclosures
(Dollars in Millions)
<S> <C>
As of December 31,
1999(3)
-------
Total balance of mortgage loans serviced.......................... $3,870
Percentage of mortgage loans delinquent by
Period of delinquency(1)(2)
30 to 59 days................................................... 4.03%
60 to 89 days................................................... 1.19
90 days or more................................................. 0.30
----------------
Total percentage of mortgage loans
Delinquent(1)(2)................................................ 5.52%
In foreclosure (excluding Bankruptcies)........................... 1.11
In bankruptcy..................................................... 1.15
----------------
Total(2).......................................................... 7.78%
----------
(1) Delinquency information is for conventional loans only, excluding bankruptcies.
(2) Percentages are based on the number of mortgage loans.
(3) A weighted average of the "MBS method" for conventional loans and
the "ABS method" for subprime loans is
used in calculation of delinquency percentage. Under the MBS
methodology, a loan is considered delinquent if any payment is past due
one or more days. In contrast, under the ABS methodology, a loan is
considered delinquent if any payment is past due 30 days or more. The
period of delinquency is based upon the number of days that payments are
contractually past due (assuming 30-day months). Consequently, under the
ABS methodology, a loan due on the first day of a month is not 30 days
delinquent until the first day of the next month.
</TABLE>
The information contained in the tables entitled "Mortgage Rates -
Pool 2" and "Cut-off Date Scheduled Principal Balances - Pool 2" under the
heading "Description of the Mortgage Pools - Pool 1 Mortgage Loans" on pages
S- 39 and S-41 of the Prospectus Supplement is hereby updated to indicate, as
of December 31, 1999, the Mortgage Rates and Mortgage Loan Balances of only
those Mortgage Loans serviced by Aurora Loan Services Inc.:
<TABLE>
<CAPTION>
Mortgage Rates - Pool 2
<S> <C> <C> <C>
Percentage of
Mortgage Loans
Aggregate by Aggregate
Range of Number of Scheduled Scheduled
Mortgage Rates (%) Mortgage Loans Principal Balance Principal Balance
- ------------------------------------------- -------------- ----------------- ------------------
<=7.000.................................... 5 $ 3,518,002.48 22.33%
7.001 to 7.500....................... 12 6,765,679.94 42.94
7.501 to 8.000....................... 2 1,116,770.65 7.09
8.001 to 8.500....................... 10 4,248,547.06 26.96
9.001 to 9.500....................... 1 108,000.00 0.69
-------------- ----------------- ------------------
Total.................... 30 $15,757,000.13 100.00%
============== ================= ==================
The weighted average Mortgage Rate is approximately 7.57% per annum.
</TABLE>
<TABLE>
<CAPTION>
Cut-off Date Scheduled Principal Balances - Pool 2
<S> <C> <C> <C>
Percentage of
Mortgage Loans
Aggregate by Aggregate
Range of Number of Scheduled Scheduled
Scheduled Principal Balances ($) Mortgage Loans Principal Balance Principal Balance
- ------------------------------------------- -------------- ------------------ -----------------
1 to 50,000.00............... 1 $ 50,000.00 0.32%
50,000.01 to 100,000.00............... 2 131,300.01 0.83
100,000.01 to 150,000.00............... 2 256,000.00 1.62
150,000.01 to 200,000.00............... 1 194,000.00 1.23
200,000.01 to 250,000.00............... 4 852,906.11 5.41
250,000.01 to 300,000.00............... 2 592,389.79 3.76
300,000.01 to 350,000.00............... 1 334,728.00 2.12
400,000.01 to 450,000.00............... 1 445,183.04 2.83
450,000.01 to 500,000.00............... 4 1,958,769.60 12.43
Greater than 500,000.00............... 12 10,941,723.59 69.44
-------------- ------------------ -----------------
Total 30 $15,757,000.13 100.00%
============== ================== =================
The average Cut-off Date Scheduled Principal Balance is approximately $525,233.34.
</TABLE>
