Dear Market Participants:

Methodology used in developing the NYISO Virtual Bidding Credit
Requirements:

Day Ahead Market Hourly Zonal LBMP and Real Time Market Integrated Hourly
Zonal LBMP values were used as the data source for developing the NYISO
Virtual Bidding Credit Requirements.  These values are available on the
NYISO web site.  The time period of June 1, 2001 through August 31, 2001
was used.  Peak hours are defined here as the hours of 6am (06:00) through
and including 10pm (22:00).  The absolute value of the difference of the
DAM and R/T price was calculated for each peak hour.  The 97th percentile
of these series of prices was calculated for each zone.  The maximum of
these zonal 97th percentiles was calculated to be $159.33.  The data
manipulation and calculation was performed in MS Excel. The attached
spreadsheet contains the data used in the June 2001 to August 2001
calculations.


(See attached file: Virt Bidding Credit Req data.xls)


Please contact the Customer Relations department with any questions.

Regards,
Customer Relations
518-356-6060
 - Virt Bidding Credit Req data.xls