market_relations@nyiso.com writes to the NYISO_TECH_EXCHANGE Discussion List:

Dear Market Participants

Billing Data Dictionary version 15.1 is now posted to the web,
replacing v15. An error in v15 was found and corrected. Version 15.1
will be effective for November billing dates forward.

The new dictionary will be posted at:
http://www.nyiso.com/markets/billing.html#datadict

If you have any questions, please call your Customer Relations
Representative or the Help Desk at 518.356.6060.

Regards,

Customer Relations