X-11/Y2k Monthly Seasonal Adjustment (Census Method II) - Trading Day Regression Tab

Select the Trading Day Regression tab of the X-11/Y2k Monthly Seasonal Adjustment (Census Method II) dialog box to access options to specify trading day regression and series adjustments.

Element Name Description
Trading day regression & adjustment of series Use the options in the Trading day regression & adjustment of series group box to determine whether and how a least-squares trading-day adjustment will be included in the analysis. Different months consist of different numbers of trading-days (i.e., Mondays, Tuesdays, etc.), which can greatly affect the monthly values (see X-11 Census Method II Seasonal Adjustment for details).
No adjustment If the No adjustment option button is selected, then no automatic trading-day adjustment is performed.
Compute only If the Compute only option button is selected, then the trading-day weights are computed and reported; however, the series will not be adjusted by these weights.
Compute & adjust series If the Compute & adjust series option button is selected, then the trading-day weights are computed (starting with the year indicated, see below) and applied to adjust the input series (starting with the year indicated, see below).
Compute & adjust conditionally If the Compute & adjust conditionally option button is selected, then the trading-day weights are computed (starting with the year indicated, see below) and applied to adjust the input series (starting with the year indicated, see below). However, in part C of the analysis (see X-11 Result Tables) the trading-day weights are only used if they explain statistically significant variation.
Start estimation at year, Adjust beginning at year The Start estimation at year and Adjust beginning at year boxes determine which years of the input series are used to compute the trading-day weights (by default all years), and to which years they are applied (by default to all years). You can enter either four-digit years in the range from 1901 through 2099, or two-digit years in the range from 0 through 99. If you specify a two-digit year less than 20, the respective year will be interpreted as 20xx, where xx stands for the two-digit year (e.g., 11 will be interpreted as 2011); if you specify a two-digit year greater than or equal to 20, then the year will be interpreted as 19xx, where xx stands for the two-digit year (e.g., 55 will be interpreted as 1955).
Sigma limit for excluding extreme values If trading-day regression is requested, then the value specified in the Sigma limit for excluding extreme values box determines how outliers in the irregular component are to be treated. Specifically, all irregular values are excluded from the computations if they deviate from 0 (additive model) or 1 (multiplicative model) by more than x * σ [where x is the value entered and σ (Sigma) is the estimate of the trading-day standard deviation].