"Coming out of the great crash of '87, we were looking at signs that the actual economy was getting better," said Jim Cramer on CNBC's "Stop Trading!" segment on Wednesday. Indicators he looked at then and is looking at again now include caustic soda, polyvinyl chloride and chlorine.

"All of those are steaming," he said. "We've got a bunch of positive chatter and upgrades on

PPG

(PPG) - Get Report

," a stock Cramer owns for his

Action Alerts PLUS

charitable trust.

"We are at last to the point where even those products are moving up," he said. "That's a sign that the real economy is back."

As for commercial real estate, Cramer noted that that the tax code has changed. "My friend buddy pal Tim Geithner the other day changed the rules," he said. "A lot of the guys who are caught up in bad real estate deals" can now use the tax code to undo some of the contracts "that have been unbelievably difficult to undo."

Some are playing this with

Annaly

(NLY) - Get Report

and

Capstead

(CMO) - Get Report

, he said, but he likes heavily shorted ETF

iShares Dow Jones U.S. Real Estate

(IYR) - Get Report

.

At the time of publication, Cramer was long PPG.

Jim Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. To see his personal portfolio and find out what trades Cramer will make before he makes them, sign up for

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