A rise in the number of new houses under construction, as occurred in November, surely means the economy is about to boom. A fall in retail sales, which occurred at the same time, surely means the economy is cooling off.
Orders for goods that people keep for several years, such as cars and refrigerators, rose in September. They fell in October. In the first half of December, the number of people filing new claims for unemployment increased.
But what do the statistics mean? Which ones are important? And do any of them reliably predict the future of the economy? Is a recession ahead? Has it already begun?
Piece by piece, the thousands of economic statistics that the federal government and private industry tabulate every month help paint the picture of the national economy that drives financial decisions by individuals, businesses and government.
"I think of it as a huge jigsaw puzzle with tiny little pieces, and every day I get a couple of new ones," Stuart Hoffman, chief economist with PNC Financial Services Group in Pittsburgh, says of the steady stream of economic reports.
"In the real world, it's a changing puzzle. It's not like you solve it and you're done."
Different statistics come in and out of fashion with the economic cycle. A decade ago, economists lived and died by the Federal Reserve Board's measures of money supply, its estimate of the total amount of money in the economy. Now, says Hoffman, few economists give it much weight.
Individual investors can't easily know which statistics are important - unless their stock portfolios soar or plummet on the release of the data. And paying attention to every newly released statistic is almost a guarantee of confusion.
"Watching high-frequency data can be dangerous to your health," says David Wyss, chief economist for Standard & Poor's Corp. in New York. "I think every day, something comes out."
Economists, though, do agree on the importance of a half-dozen statistical indicators, in times of growth as well as recession.
These are the measures that seem to reliably describe the state of the economy and, over time, hint at its direction:
Employment Situation report. If economists had to choose a favorite measure, this likely would be it. "It has a lot of numbers in it, a lot of stuff to analyze," says Wyss.
Released by the Department of Labor on the first Friday of the month, it is the first major indicator of what happened the previous month. As such, it can move the stock markets.
Important numbers: How many jobs were gained or lost, the jobless rate and average hourly earnings (this last item being an inflation gauge).
The report is compiled from two surveys: The Current Employment Statistics, which surveys 380,000 nonfarm businesses on number of workers, wages and work hours; and the Current Population Survey, which is conducted by 1,500 Census Bureau workers interviewing members of 50,000 households about their work status.
Gross Domestic Product. "It is really the most comprehensive picture of the overall economy," says Sung Won Sohn, chief economist for Wells Fargo & Co. in Minneapolis.
Released quarterly by the Commerce Department, the GDP is the market value of all goods and services produced within the United States. Changes in GDP show how fast or slow the economy is growing.
To calculate the GDP number, about 100 staffers in the Bureau of Economic Analysis collect and organize thousands of economic figures compiled by private sources and government agencies. The data fall into four categories: consumer spending, net exports, business investment and government spending and investments.
The Commerce Department was asked to track industrial production in the late 1930s, when it appeared the country was headed for war and the government wanted to assure enough resources were available.
Consumer Price Index. Calculated monthly by the Bureau of Labor Statistics, this cost-of-living index measures changes in the prices that urban consumers pay for a selection of good and services. Critics say the CPI tends to overstate inflation and doesn't accurately reflect today's shopping habits. But it is the most widely watched inflation gauge.
The CPI was created during World War I because a rapid rise in prices created a need for an index to make cost-of-living adjustments in wages. Data collection began in 1917 and the CPI was issued beginning in 1919.
About 275 field representatives visit stores, apartments and businesses in 87 cities each month to record prices of 80,000 items - including eyeglasses, gasoline, rent, cupcakes, beer, breakfast cereal, tuition, software and funeral services. The basket items have been revised every 10 years, based on consumer diaries. Beginning 2002, the basket will be updated every two years.