The Chicago Fed National Activity Index (CFNAI) is a monthly index designed to better gauge overall economic activity and inflationary pressure. The CFNAI, which is a weighted average of 85 existing monthly indicators of national economic activity, is constructed to have an average value of zero and a standard deviation of one. Since economic activity tends toward trend growth rate over time, a positive index reading corresponds to growth above trend and a negative index reading corresponds to growth below trend. The 85 economic indicators that comprise the CFNAI are drawn from five broad categories of data: output and income; employment, unemployment and hours; personal consumption, housing starts and sales; manufacturing and trade sales; and inventories and orders. Each of these data series measures some aspect of overall macroeconomic activity. The derived index provides a single, summary measure of a factor common to these national economic data.