What was going on when I was born?

A reviving economy, lower interest rates and drastically pared operating costs are beginning to have a healthy impact on corporate profitability. All the results for the first quarter are not yet in. Major retailers and the oil companies, which account for about one-third of corporate profits, have not begun to report, for example. But earnings reports released thus far have led economists and other analysts to project that after-tax profits in the first quarter are likely to register the first year-to-year increase since the second quarter of 1981.

After President Reagan pulled Paul A. Volcker aside last Wednesday to apologize for news stories suggesting that he would be let go as chairman of the Federal Reserve Board, two things became apparent to aides and economists close to the President. First, according to one official, was that the President - as he told Mr. Volcker - genuinely has not made up his mind about whether to replace the Fed chairman when his four-year term expires Aug. 6. And second was that Mr. Volcker, if asked to continue on the job, would likely accept. These days, when it comes to Mr. Reagan's intentions toward the Fed, speculation and sifting of clues like last week's exchange with Mr. Volcker - which occurred after a meeting of the President's Economic Policy Advisory Board - are about all there is to go on.

International Austria's Socialist Party lost its clear majority in Parliament in national elections, and Chancellor Bruno Kreisky announced that he had decided to resign after 13 years in office. His party lost 5 seats, from 95 to 90, in the 183-seat Parliament, depriving it of the clear majority it had held since 1971. Nevertheless, the Socialists, who received 47.8 percent of the vote, remain a commanding force in Parliament. (Page A1, Column 6.) Soviet and American weapons were in the cargo carried by one of four Libyan planes that landed in Brazil last week, a Brazilian spokesman said. The planes, which were originally said to have been carrying medical supplies for Nicaragua, were detained after it was discovered that they were carrying military supplies as well. (A1:4.)

Chancellor Bruno Kreisky's Socialist Party lost its clear majority in Parliament in national elections today, and the Chancellor said tonight that he had decided to resign. Mr. Kreisky has governed Austria and dominated its public life for 13 years, longer than any other current head of government has been in power in the West. His announcement came after election results showed that his party had lost 5 seats, from 95 to 90, in the 183-seat Parliament, depriving it of the clear parliamentary majority it had held since 1971. Despite their reversal, the Socialists, who took 47.8 percent of the popular vote, remain the commanding force in Parliament. With 43.2 percent of the vote, the centrist People's Party increased its share by 4 seats, to 81.

An article in Business Day April 13 about insider trading in stock options misstated the title and provisions of the Securities Exchange Act of 1934. Section 16(a) requires officers, directors and principal shareholders of publicly held corporations to disclose their trading in their company's shares. Section 16(b) requires that if they profit by buying and selling the shares within a six-month period, they turn over such ''short swing'' profits to the company.

The Economy First-quarter corporate profits are likely to show their first gain on a year-to-year basis since the second quarter of 1981, according to economists. The expected increase is attributed mainly to a reviving economy and lower interest rates and operating costs. (Page D1.) Bank holding company earnings held up well in the first quarter, despite mounting loan losses. (D1.)

A firebomb was thrown into a ground-floor office of the Justice Department's environmental crimes unit Sunday night, causing minor damage. The environmental unit's chief prosecutor said today that he believed his adjoining office had been ransacked. Investigating authorities, however, said his papers were disturbed by firefighters. An official of the Federal Bureau of Investigation said the throwing of the firebomb might have been a random attack.

THE year 1954 was such a good one for college quarterbacks that four - Bobby Garrett, Lamar McHan, Cotton Davidson and Bernie Faloney - were selected in the first round of the National Football League draft. That had happened only twice before, in 1949 with John Rauch, Stan Heath, Bobby Thomason and Frank Tripucka, and in 1952 with Bill Wade, Babe Parilli, Larry Isbell and Harry Agganis. They were the only years in which that many quarterbacks were picked in the first round. Since 1973, talent pools, scouting reports and team needs have been such that first-round picks have been used for quarterbacks only 14 times and only once, in 1979, were as many as three selected - Jack Thompson by Cincinnati, Phil Simms by the Giants and Steve Fuller by Kansas City. In 1974, no quarterbacks were picked in the first round. The first round of the N.F.L.'s 48th annual draft, which will be conducted tomorrow, figures to be different. Most experts agree that four quarterbacks will be among the 28 selections in the first round, and many have predicted that five will go. They are John

Doug Kuehl's day at the Boston Garden ended much too soon, some 20 minutes after the Celtics abruptly ended the season of the Atlanta Hawks. Kuehl, a 21-year-old security guard at Boston's Logan International Airport, was in no hurry to leave. There was still a show to see. ''I'd really like to see the Bruins play the Sabres,'' said Kuehl, remaining in the near-empty stands to watch the Garden's ''Bull Gang'' dismantle the Celtics' parquet floor and prepare for the hockey game. ''But I can't afford two games. I had two seats for this, at $9.50 apiece, and couldn't sell the other.

A man's body recovered earlier this month from a New York State lake has been identified as that of a missing former General Motors executive who had extensive business contacts in Europe and South America. He had three bullets in his head and weights attached to his legs. The state police have opened a broad investigation into the circumstances of his disappearance from a midtown Manhattan hotel last January and his subsequent murder. The businessman, George M. Perry, 64 years old, disappeared from the Grand Hyatt Hotel in New York City in January, leaving behind $2,000 in American and Brazilian money in a hotel safe-deposit box. At his disappearance, he was working as an international trade consultant for a Brazilian company.

Skepticism over the authenticity of Hitler's purported diaries widened yesterday among historians, former aides of the dictator and handwriting experts in Britain, West Germany and the United States as the first excerpts were published. Disbelief was expressed by David Irving and Lord Bullock, British historians and experts on Hitler; Werner Maser, a West German historian; two of Hitler's former personal aides, and Charles Hamilton Jr., an American expert on handwriting who has just completed an 800-page, two-volume study called ''Autographs of the Third Reich.'' ''I'm sure it's a hoax,'' Mr. Hamilton said in an interview in New York yesterday after seeing three photostatic sheets from the purported diaries, including two bearing Hitler signatures. ''The whole story is a misbegotten prevarication. The forgers are probably luxuriating right now in the south of France.''

The Long Island Rail Road will soon begin a multimillion-dollar renovation of its platforms and waiting space in Pennsylvania Station, one of the nation's busiest terminals. The work, which will cost $22.6 million, will be the station's first major renovation since the old Pennsylvania Station was torn down and replaced by the Madison Square Garden complex in the mid-1960's. The Long Island waiting area was expanded then by the Pennsylvania Railroad, which owned the station. The new work is needed because rush-hour traffic has increased dramatically in recent years, and because a new train-storage yard being built near Pennsylvania Station may significantly increase traffic within the next three years, railroad officials said.