The big macro can cause big moves in the market. What does today's headline macro news mean for your portfolio?

What’s happening: Chicago's Institute for Supply Management released its purchasing managers' report for October, and the numbers were short of expectations but were still in positive territory.

In plain English, please: Faltering manufacturing numbers have been a concern for investors and economist for months now, and the Chicago PMI report doesn't do a whole lot to allay those worries. The Chicago Business Barometer's three-month moving average fell for the seventh consecutive month, and the reading of 58.4 was below the 58.9 that economists were looking for.

However, any reading above 50 is an expansionary reading ,and among business activity indicators in the report, employment was the highest in six months and order backlogs recovered from a two-month contraction.

Stocks to watch: In light of this release, there may be reason to look at specific manufacturing companies based in the region around Chicago -- for instance, Caterpillar (NYSE: CAT), 3M (NYSE: MMM), Ford (NYSE: F), and Illinois Tool Works (NYSE: ITW). However, the health of the manufacturing sector is a key indicator for gauging the broad health of the U.S. economy, so even investors not heavily invested in manufacturing companies should take note of this report.

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