How do I interpret the symbols (for example, an *) in the Benchmark Tables?

The December 2002 Survey of Current Business (SCB) article on the 1997 I-O accounts, “Benchmark Input-Output Accounts of the United States, 1997,” explains all the definitions and conventions used in the creation of the accounts.  The article is available online at http://www.bea.gov/scb/pdf/2002/12December/1202I-OAccounts2.pdf.  Subsequent changes in classification and definition can be found in the October 2007 SCB article “U.S. Benchmark Input-Output Accounts, 2002,” available online at http://www.bea.gov/scb/pdf/2007/10%20October/1007_benchmark_io.pdf.