Retail inventories extended their climb in August, rising 1.1 percent and led by a 2.3 percent build in vehicles. Total retail inventories are up 4.5 percent on the year but fall to a 1.4 percent draw when excluding the 22.2 percent pent-up vehicle build underway. On the month, retail vehicle inventories rose 2.3 percent in August.

Retail inventories measure the monthly dollar value of inventories held by retailers. The advance report is released late in the month for the following month and is part of the Monthly Advance Economic Indicators report (which also includes data on wholesale inventories and international trade in goods). Final monthly data for retail inventories are released about two weeks later with the Business Sales and Inventories report.

Investors need to monitor the economy closely because it usually dictates how various types of investments will perform. The stock market likes to see healthy economic growth because that translates to higher corporate profits. The bond market prefers a slower rate of growth that won't lead to inflationary pressures. Retail inventory data give investors a chance to look below the surface of the visible economy, especially for unwanted build. If inventories are growing too fast relative to economic growth, then both production and employment will probably have to slow while those inventories are worked down.