Sears, Roebuck and Co. today reported a dramatic improvement in profits for the first quarter of its fiscal year, but executives of the nation's biggest retailer said consumers still are not spending like they used to.

Sears earned $94.2 million (30 cents a share) in the three months ended April 30 compared with $59 million (19 cents) in the same period last year, board Chairman Edward Telling reported at Sears' annual shareholders meeting here.

Nearly half the gain resulted from a change in the way Sears pays federal income taxes, but Sears' sales jumped 13 percent in March and 20 percent in April, and first-quarter revenues increased to $6.1 billion from last year's $5.5 billion.

"The first quarter was better than we expected it to be, yet I don't think anybody could say the economy is any stronger right now," said Edward A. Brennan, chairman and chief executive of Sears retail operations.

Brennan said Sears now has posted six months of improved sales in a row, an indication that Sears has solved some of the operating problems that forced the company to cut back sales promotion efforts in an effort to rebuild profits.

"There are definite signs that our strategy is working," Brennan told stockholders. "In the first quarter, we outperformed virtually all our major competitors."

Sears now is "ready to take advantage of an upturn in the economy," added Brennan, who took over in January as head of Sears' $18.7 billion-a-year retailing empire.

Sears executives repeatedly stressed that consumer spending has not recovered from a downturn that began with the imposition of credit controls by the Federal Reserve Board in March.

"A full recovery continues to elude us," said Brennan, whose stores sell more merchandise to consumers than any others in the world and whose sales provide an important reflection of the spending habits of middle-class Americans.

Sears' stores and catalogue sales in the United States and abroad and their related consumer credit operations produced revenues of $4.4 billion in the first quarter, up 11.3 percent from the $3.9 billion of the same period a year ago.

The retail operations earned a profit of $17.4 million for the quarter, in contrast to an $18.3 million loss last spring, when sales were seriously depressed.

Sears' big moneymaker was the Allstate insurance group, which earned $110 million, enough to offset losses on credit and foreign operations and pay corporate overhead.

The company also reported a $4.1 million profit from its Seraco group, which includes the Homart shopping center development company, Allstate Savings and Loan in California and mortgage banking and other financial services operations. Effective in January, Sears reorganized it operations into three groups -- retailing, Allstate and Seraco.

Retailing now is two-thirds of Sears' business. The other two divisions will be expanded substantially, but Telling refused in a press conference to estimate how much of Sears' business they eventually will account for.

Allstate -- which is the nation's second-largest personal property and liability insurance company and which ranks 12th in new personal life insurance -- is expanding into other insurance lines, said Archie Boe, chairman of that group. A year ago Sears began moving into the commercial property and liability market, and it also is planning to build up its group life and health insurance operations.

The Seraco group, headed by President Martin, is now the third-largest shopping center developer in the country. It will open four major malls this year, including one in the Portsmouth, Va., area. Martin said Seraco plans a series of office-park developments in partnership with other major corporations and will start building "convenience shopping centers" with supermarkets drugstores and other outlets in an effort to expand into smaller communities where there is no room for a major mall.

After the stockholders' meeting, Sears directors announced a decision to change the company's fiscal year to conform to the calendar year. Like most retailers, Sears until now has reported results for a year ending Jan. 31 to show the impact of after-Christmas sales.

Switching to a calendar year will make it easier for Sears to consolidate its retail operations with the increasingly important nonretailing businesses, which usually do their accounting on a calendar-year basis.