Go to the St. Louis Federal Reserve FRED database, and find data on real private domestic investment (GPDIC96), real residential investment (PRFIC96), and real non-residential (business) fixed investment (PNFIC96).

a) Using these data, calculate inventory investment for the most recent quarter of data available.

b) For each quarter since 2000, calculate the percentage of inventory investment as a share of total investment, and then calculate, from 2000 to the most current quarter of data available, the average percent share of inventory investment relative to investment. Is this number zero? Does the average over this time support the idea that inventories have benefits? Why or why not?