When the opening bell rang at the New York Stock Exchange Tuesday morning, it signified a historic day for the U.S.economy. It marked the 107th month in a row that the economy has expanded--almost 9 years--the longest uninterupted run of economic growth in U.S. history. The previous record, 106 months, was set back in the 1960s.

And there are no signs that things are slowing down. In fact, the latest reports in the U.S. show that consumers are boosting their spending at twice the rate that their incomes are growing.

However, all this good news is proving worrisome for central bankers like Alan Greenspan. The economy would appear to be facing a classic recipe for rising inflation. That means higher interest rates are almost guaranteed when Fed board members meet Tuesday and Wednesday. But the Fed doesn't want to spoil the economic party.

As CIBC senior economist Josh Mendelsohn told Newsworld Business News, "If they tighten too much, they could prevent desirable investment. If they tighten too little, they could find themselves facing inflation and a loss of confidence."

Concern about what the Fed will do was widely evident in a steep sell-off on the Hong Kong market Monday morning. North American markets managed to overcome the jitters experienced on Friday with some gains. But there's no question investors around the world are nervous that rates could rise more than the anticipated 25 basis points.

And the U.S. will be just the start of a worldwide trend toward higher rates. Economists are nearly united in their belief that the Bank of Canada will match any hike by the Fed. And it's expected the European Central Bank will also push up rates, perhaps as early as this Thursday.