The measure of year-over-year growth in tax withholding is updated daily, although only about half of the business days contain data that can be filtered appropriately to yield a useful daily measure. Fortunately, we know in advance nearly all of the days that will yield a representative measure that we can use.  The expected days for the current month are listed below. The data on withholding for a day are released by the U.S. Treasury Department generally at 4:00 PM ET on the day after the amounts are remitted by employers, and we update the measures shown on this site generally by 4:15 PM ET on that day. See the methodology page for more information on the days that are generally excluded.