The ISM Report On Business has its roots in the 1920s when N.A.P.A. began polling its members about commodities. During the Great Depression, N.A.P.A. began supplying economic data to President Hoover and the importance of the report has grown to its present significance. Today, it is considered to be one of the most reliable economic barometers of the U.S. economy and gives an important early look at the health of the nation’s economy. The Report is based on two national surveys of purchasing managers tracking changes in the manufacturing and non-manufacturing sectors.