X11 output B 17 - Preliminary Weights for Irregular Component

The estimates of the irregular component (in B 13 or adjusted by B 16 , depending on whether or not a trading-day adjustment was performed) are further refined by computing graduated weights for extreme values, depending on their relative (in terms of a sliding 5-year s) distance from 0. Specifically, a process analogous to that described in B 4 above is used. This X-11 table (B17) contains the resulting adjustment factors.
For more information, see X-11 Census Method II Seasonal Adjustment .