More is Less: Tax Gap Study Shows Increased IRS Efforts Yielded Lower-than-Expected Returns 

This article, More is Less: Tax Gap Study Shows Increased IRS Efforts Yielded Lower-than-Expected Returns, shows the increase in compliance activity to close the tax gap. The tax gap is the amount of tax dollars lost to the US Treasury each year due to taxpayer noncompliance.  The tax gap is almost a ½ a trillion dollars a year.  The IRS is tasked with closing the tax gap.