What was going on when I was born?

New orders for domestic machine tools improved modestly in February from January, but were down sharply from those in February 1982, the National Machine Tool Builders' Association said yesterday. Economists consider statistics on machine tool orders, shipments and order backlogs as indicators of the domestic industry's production plans. But the steadily rising volume of imported machine tools has clouded this economic barometer.

New York City's buses break down four times as often as those on the streets of Los Angeles and Chicago, according to an audit released yesterday. But the Transit Authority responded that the three cities were not comparable. And, according to a second audit on bus air-conditioning, more of New York's buses are hot than cool during the summer months. The Transit Authority did not dispute this.

Hundreds of thousands of pounds of carp from Saginaw Bay in Michigan, samples of which have been found to contain residues of the chemical dioxin, are annually shipped to markets in New York, Chicago and other Northern cities. The Federal Food and Drug Administration says that it has not found reason to stop interstate trade in the fish. But the Michigan Department of Health has issued warnings that consumption of such fish should be limited. About a third of the fresh carp sold in New York City comes from Saginaw Bay, according to wholesalers. Asked whether the fish should be eaten, the New York City Health Commissioner said people should follow guidelines issued by the State Health Department on consumption of fresh-water fish caught in New York State. The guidelines say that no more than one meal a month of fresh-water fish should be eaten and that pregnant women, women of child-bearing age, nursing mothers and children under 15 years old should not eat such fish.

Integration came no more easily to the corner of this city known as Cramer Hill than to any other part of America. But over the last 10 or 15 years, come it did. Blacks moved beside Germans, Hispanic people next to the Irish, and though some people fought, others accepted, even befriended, their new neighbors. Now all that is being tested by the death of a little boy. Seven-year-old George DeCasonova was Hispanic. Gerald Gerlock, the young man who hit him with his car on March 15, and who grew up in this neighborhood, is white. Such a circumstance worried people enough in Cramer Hill. And then, last Friday, Camden County authorities charged that the accident was no accident, and that Mr. Gerlock had driven his car into the boy after telling passengers that ''the lives of minorities - blacks and Hispanics - had a certain point value to him,'' according to Dennis Wixted, an assistant county prosecutor.

Business profits, widely regarded as a ready barometer of the pulse of an economy, recently have been a cause for alarm, particularly among those who would like to see increased investment and growth. Most economists do, of course, look for sizable increases in profits as the economy recovers. But just how substantial the rise will be is a matter of much debate. What concerns some analysts is that corporate profitability appeared to be on a long downward slide even before the United States entered the recent recession and could be continuing despite the temporary upturn that comes with recovery. ''As I look at the data, it is very clear that in the United States, and in other industrial countries, there has been a remarkable decline in the return on capital,'' said William B. Nordhaus, a professor of economics at Yale University. He said 1982 was the year of lowest profitability, but noted that ''over the past 10 to 12 years, profits of American corporations have been markedly lower than they were in earlier years.''

Less than two weeks after the Organization of Petroleum Exporting Countries cut prices by $5 a barrel, some oil exporting nations are starting to line up for money from the International Monetary Fund and commercial banks. The actions of such countries as Venezuela, Ecuador and Nigeria follow reports that Mexico, a non-OPEC member that recently signed a $10 billion I.M.F.-designed loan package, may need an additional $2 billion this year because of lost oil revenues. Mexico could see its oil revenues fall by $3 billion this year as a result of lower oil prices, some officials have estimated. But Treasury Secretary Donald T. Regan and international monetary authorities based here insisted last week that the situation is manageable.

The Legislature approved a 1984 tate budget early today calling for $220 million in added programs, but thousands fewer layoffs, than Governor Cuomo's original proposal. The budget, arrived at after weeks of negotiations, imposes nearly $1 billion in new taxes. Overall, it would add less than 1 percent to the Governor's proposed $31.5 billion budget. The last bill was passed in the Assembly shortly before 2 A.M. today, and in an unusual show of unity, Assembly Speaker Stanley Fink, Democrat of Brooklyn, invited Governor Cuomo and the Senate majority leader, Warren M. Anderson, a Binghamton Republican, to the podium to speak. 'Proud of When We Did It' ''I'm not particularly proud of what we have done.'' Senator Anderson said. ''But I am proud of when we did it.'' Governor Cuomo said, ''What you produced is a better budget than the one I gave you, and for that I am grateful.'' Assemblymen who had debated for most of Sunday and into the morning cheered wearily. The Senate had completed action about an hour earlier. As the final bill, a measure imposing a series of taxes, was put to a vote, Senator Anderson walked over to several Republicans who voted against the measure, including Senator John E. Flynn of Yonkers and Senator Martin J. Knorr of Queens. They immediately changed their votes. The measure passed by a vote of 48-12.

Nicaraguans described as insurgents fighting to overthrow the Sandinist Government in Managua appear to be operating from a camp in the hills above this hamlet near the border. The camp, to which a reporter was directed on Saturday by local residents, is in the province of El Paraiso, about a mile off a dirt road that runs from the border village of Cifuentes to the region's principal town, Danli. It is about eight miles from the border with Nicaragua if one walks overland, according to nearby residents. The encampment consisted of more than a dozen large tents, near an earthen hut packed to the rafters with unopened crates labeled as United States-made armaments. According to English markings on the crates, their contents included fragmentation grenades and mortar shells.

With an orange light blinking and a tinny speaker blaring a John Philip Sousa march to warn the unwary, a driverless forklift truck goes mindlessly about its business of picking up loads of formed metal sheets, fresh from stamping machines, and carrying them about 50 feet to where they will start becoming Honda cars, vans and light trucks. The automatic truck in the Honda Motor Company's sprawling manufacturing complex here does the same things a manned vehicle could do, but it quite possibly does them faster and with more adaptability. It is indicative, though, of this country's attitude toward automation, particularly in the automobile industry. The Japanese auto companies do not just use automation as a tool: They revel in it. Engineers at auto plants here beam with pride as they show off engine production lines that process raw castings into finished parts, untouched by human hands. Automatic transfer arms, not people, stand between the machines in stamping lines, smoothly moving body panels hour after hour without faltering.

Martina Navratilova said it ''was pretty close to as good as I can play,'' and Chris Evert Lloyd did not argue. ''She really cleaned my clock,'' Mrs. Lloyd told a Madison Square Garden crowd of 13,244 yesterday, after having been beaten, 6-2, 6-0, by the top-seeded Miss Navratilova for the $80,000 first prize in the Virginia Slims of New York tennis championships. The loss was Mrs. Lloyd's most lopsided in 950 singles matches on the tour, spanning more than 13 years. It was inflicted by a confident, aggressive rival who swept 10 games from 2-all in the opening set, and whose record in the last 15 months has been extraordinary.

The Board of Estimate is approaching a difficult decision on the monthly payments of the 46,000 Mitchell-Lama housing tenants in New York City. On June 30 the board can force a $30 raise in the payments - in which any increase is opposed by the tenants - or it can renew temporary tax abatements that cost the city $14 million a year. At issue is whether the city will ever collect the taxes it expected when the projects were built and whether rises in rent and maintenance costs would drive out the middle-income residents for whom the program was intended. The decision is important both to the Mitchell-Lama tenants, a group that experts in housing say is well-organized, and to the city, which is facing financial stringency.

The United States accused Yuri V. Andropov today of making a ''false allegation'' in contending that the Reagan Administration sought military domination over the Soviet Union. It also said the Soviet leader had distorted the intent of President Reagan's plan for research on a defense system against missiles. In a formal response to Mr. Andropov's remarks, the State Department expressed ''regret'' over the ''tone and content'' of the Soviet leader's charges. Mr. Andropov, responding to Mr. Reagan's speech Wednesday night, said that the United States was trying to become ''the world's dominating military power'' and that Mr. Reagan had made ''impudent distortions'' of Soviet military policy. Mr. Andropov's remarks were published as an interview in the Communist Party daily Pravda and distributed Saturday by the official press agency Tass.