American Community Survey (ACS)

Disclosure Review Board Rules/Requirements

1. All American Community Survey Custom Tabulations must be reviewed by the Disclosure Review Board. After the tabulation has been created, if the program area identifies any potential disclosure problems, they will refer them back to the DRB.

2. All cells in any American Community Survey Custom Tabulation must be rounded.

   The rounding schematic for all tables is:

   • 0 remains 0
   • 1-7 rounds to 4
   • 8 or greater rounds to nearest multiple of 5 (i.e., 864 rounds to 865, 982 rounds to 980)
   • Any number that already ends in 5 or 0 stays as is.

   Any totals or subtotals needed should be constructed before rounding. This assures that universes remain the same from table to table, and it is recognized that cells in a table will no longer be additive after rounding.

3. Medians or other quantiles may be calculated as
   
   
   1. an interpolation from a frequency distribution of unrounded data (these are not subject to additional rounding), or
   2. as a point quantile. These must be rounded to two significant digits: 12,345 would round to 12,000; 167,452 would round to 170,000. There must be at least 5 cases on either side of the quantile point.

   It is recognized that a quantile may indeed be some individual's response, but it is coincidental, not by design.

4. Thresholds on universes will normally be applied to avoid showing data for very small geographic areas or for very small population groups (often 3 or 50 unweighted cases). Tables may normally not have more than 3 or 4 dimensions, and mean cell size lower limits may also be required (mean cell size of each table is 3 unweighted cases).

5. Percents, rates, etc., should be calculated after rounding, but the DRB has granted exceptions to this rule when the numerator and/or denominator of the percent or rate is not shown.

6. Means and aggregates must be based on at least 3 values.

7. The finest level of detail shown for Group Quarters data will be Institutional/ Noninstitutional.

8. For Demographic Profiles from user-defined geographic areas (neighborhoods), all areas must have at least 300 (weighted) people in them. Using a computer program, the user-defined areas will be compared with standard Census Bureau areas to make sure users cannot obtain data from very small geographic areas by subtraction. If such small areas are found, the boundaries of the user-defined areas must be changed.