How are the annual levels of current-dollar industry gross output derived?

Since the 1998 comprehensive revision of the Industry accounts, an industry’s annual gross output is derived by extrapolating its gross output as reported in the BEA’s most recent (2002) benchmark input-output (I-O) accounts. For example, Information sector (NAICS 51) gross output is currently estimated by extrapolating the value from the 2002 benchmark I-O accounts with source data from the Service Annual Survey (SAS) published by the U.S. Census Bureau.