This paper describes the statistical disclosure limitation techniques to be used for all U.S. Census 2000 data products. It
includes procedures for short form tables, long form tables, public use microdata files, and an online query system for tables.
Procedures include data swapping, rounding, noise addition, collapsing categories, and applying thresholds. Procedures for
the short and long form tables are improvements on what was used for the 1990 decennial census. Several procedures we will
be using for the microdata are new and will result in less detail than was published from the 1990 decennial census. Because
we did not previously have the online query system for tables, all of those procedures are newly developed.
This paper reports the results of research and analysis undertaken by Census Bureau staff. It has undergone a Census Bureau
review more limited in scope than that given to official Census Bureau publications. This report is released to inform interested
parties of ongoing research and to encourage discussion of work in progress.