NEW YORK -- Compared with high-tech, there's nothing glamorous about aluminum, chemical products and basic manufacturing. But investors don't care because they see there's money to be made in reliable Old Economy sectors.

"When the economy gets better, you buy the things you need, not the things you want," said Arthur Hogan, chief market analyst at Jefferies & Co. "That's what's going on right now."

Indeed, investors' recent strategy has been to buy stalwart blue-chip companies, including DuPont and Caterpillar, that are showing the first signs of earnings improvement.

While tech trading might be more exciting, it's also riskier, and so investors are more or less putting the sector on hold until its recovery is more certain.

With Wall Street's latest rallies focused on blue chips, the Dow Jones industrial average has risen 7.1 percent during the past month, and on Tuesday achieved its highest closing level of the year, 10,632.35. The tech-dominated Nasdaq composite index, meanwhile, is up about 3.5 percent compared with its standing of four weeks ago.

However, not all 30 Dow stocks are participating evenly in the advance. The greatest strength has come in basic material stocks and manufacturing companies including International Paper and DuPont. The two Dow industrials are trading near their 52-week high prices.

And, now investors are boosting manufacturers such as Caterpillar and consumer cyclical companies including General Motors. Caterpillar closed Friday up $1.13 at $59.79, near its March 8 52-week high of $59.94. GM also is approaching its year-ago high.

When the economy first starts to improve, "You think of playing basic materials, diversified manufacturers, and eventually retailers," said John C. Forelli, portfolio manager for Independence Investment LLC in Boston.

Economic data also points to a recovery taking place in blue-chip sectors.

On Friday, the Federal Reserve reported the strongest industrial production numbers since June 2000 as output at the nation's factories, mines and utilities rose 0.4 percent in February. The bigger-than-expected increase is the strongest evidence yet that manufacturing is improving.

Analysts say the last sectors to rally on Wall Street will be technology and telecommunications, where companies are still issuing revenue and profit warnings.