The NYSE Group, reporting results for the first time since it became a public company, said it earned $30.3 million in the three months ended in March.

The world’s largest stock market, whose merger this year with Archipelago Holdings was the biggest transformation in its 213-year history, earned 24 cents a share, according to a statement on its Web site. NYSE said it earned $26 million, or 22 cents, a year earlier.

The Archipelago transaction will probably triple net income by 2007 as the exchange cuts costs, the NYSE said in December.

Chief Executive Officer John Thain has said he aims to use his shares to buy other exchanges, fueling merger speculation that is sweeping the world’s biggest stock markets.

“Quarter-over-quarter earnings aren’t the story right now; it’s strategic plays and who is going to pair up with whom,” an analyst at Chicago-based Morningstar, Philip Guziec, said.

Mr. Thain, 50, last month said he wants the exchange to be a leader in consolidating markets around the world. Mr. Thain’s counterpart at New York-based Nasdaq, Robert Greifeld, 48, bought 15% of the London Stock Exchange, paving the way for a potential transatlantic merger.

Shares of NYSE rose $2.65, or $3.6%, to $75.45 today.

The stock has risen 17% from the $64.25 final price of Archipelago’s shares on March 7, when NYSE merged with the electronic exchange. The results were released yesterday after stock-market trading closed in America.

The NYSE may comment on efforts to cut costs and the consolidation among securities exchanges during a teleconference with investors scheduled for 8:30 a.m. today.

A Sandler O’Neill & Partners analyst, Richard Repetto, had estimated that the company would report first-quarter profit of $38 million, or 24 cents a share. He rates NYSE shares “sell.”

Revenue excluding regulatory fees collected from brokerages rose 20% to $339.7 million, helped in part by an increase in trading and new fees. Expenses rose 31% in the quarter to $320 million.

The costs included a $37.7 million charge linked to a compensation award to NYSE employees at the time of the Archipelago merger. The exchange also had a $20.9 million gain from the sale of an equity investment.

If the Archipelago merger had been completed by the start of the quarter on January 1, the NYSE said it would have earned $37.3 million, or 23 cents a share. Revenue would have been $421 million, and expenses would have fallen 1.2% to $370 million.

Fees from stock listings, the largest source of revenue for the NYSE, rose 2.9% to $88.5 million in the first quarter. Trading fees paid to the exchange by brokers jumped 65% to $215.4 million in the period as the Standard & Poor’s 500 Index climb to a five-year high spurred an increase in equity trading in America.

Trading in NYSE-listed stocks rose 20% from a year ago, compared with an 8% increase in Nasdaq-listed stocks, according to data on the exchanges’ Web sites.

The NYSE in December increased fees paid by floor traders to use equipment and facilities, a move that could raise an additional $22.5 million in revenue annually, according to an analyst at Keefe Bruyette & Woods, Richard Herr, said. He has a “market perform” rating on NYSE.

In March, the NYSE began collecting revenue from the sale of floor-trading licenses, which will add $62.8 million in revenue over the next 11 months, according to filings with the Securities and Exchange Commission.

The NYSE last year forecast net income will more than double to $192.4 million in 2006 and surge to $293.6 million in 2007 as it reduces costs.