The following graph, created using data from the Missouri Economic and Information Center (http://www.misssourieconomy.org

The following graph, created using data from the Missouri Economic andInformation Center (http://www.misssourieconomy.org) shows the value ofthe Purchasing Managers’ Index from August 2003 to July 2005.
a. Use the Web to find how this index is calculated.
b. Describe what the graph shows in this context.