(FORTUNE Magazine) – THE CHRISTMAS PRESENT the Commerce Department gave economists this year, too heavy for a stocking stuffer, was the most comprehensive revision of U.S. income and production data in a decade. Analysts will be absorbing the mounds of new information for months, but the biggest surprise already seems clear: there are no big surprises. The revised economy is 2.7% bigger, but it has behaved very much like the old version. Since 1972, for example, GNP has grown 9.9% a year on average, exactly as the earlier data showed. Inflation-adjusted GNP averaged 2.5%, a few tenths of a percent less than previously thought. The new personal savings turned out to be a little higher than the old rate, but the improvement was less than FORTUNE anticipated. Most of the extra savings comes from better estimates of income earned legally but not reported to the tax collectors. Some analysts quibble that the revisions didn't go far enough in accounting for the underground economy, which includes everything from garage sales to cocaine deals. Still, the savings rate is lower now than at almost any time in the past. One pleasant surprise was that the economy is probably a bit less burdened with excess production capacity than the earlier data indicated. The new data show that spending for capital goods has increased much less since 1980 than thought. And capital stock recently has been growing 3% a year, not 4%. FORTUNE looks at these new numbers as confirming its forecast that capital spending will hold steady in coming months. The revisions provide a more reliable tool for analyzing current trends and forecasting future ones. Distortions in the old fixed-weighted GNP deflator, for example, added an average of 0.7 percentage point a year to the inflation rate. The indicator measured inflation as if the pattern of spending had remained the same from 1972 on. But consumers and businesses were shifting spending away from goods and services with escalating prices to those that increased less. For example, oil prices quadrupled after the 1973 oil shock, and consumption as a percentage of GNP began a decline that has yet to end. But the deflator continued to allocate the same proportion of GNP to the ever more expensive oil as it had before. With the new base year, 1982, the deflator more nearly represents today's spending patterns. Though U.S. statistics are among the best and most detailed in the world, critics argue that even after this major redo, the data give too little weight to fast-growing services such as banking and underestimate the economic contribution of such things as improved medical procedures. Gerald F. Donahoe, chief of the Commerce Department's income and wealth division, agrees. The figures undoubtedly ignore some productivity increases, he allows, but only because there's no way to measure them. Perhaps a way will be found by the time of the next big revisions in 1990.

CHART: TEXT NOT AVAILABLE REFINING THE NUMBERS The Commerce Department's revised economic statistics show that capital stock is growing 3% a year, more sustainable than the old rate. The new savings rate is only slightl better.