HOSPWT_F contains the weight to the hospitals in the frame states. There were:

• 8 frame states for 1988;
• 11 frame states for 1989-1992;
• 17 frame states for 1993-1994;
• 19 frame states for 1995-1996; and
• 22 frame states for 1997.

Beginning in the 1998 NIS, this data element is not included in the data set.

For detailed information about the development and use of discharge and hospital weights, see the year-specific report on the Design of the HCUP Nationwide Inpatient Sample.