Investors drove up the stock of the NCR Corporation, the largest maker of automated teller machines and airport check-in kiosks, yesterday after the company said it would spin off its data management business, Teradata, in what it expects to be a tax-free deal. Shares of NCR rose as much as 7.1 percent, to $45.42, before falling back to close at $43.79, an increase of $1.39, or 3.3 percent, over Friday's close. About 5.7 million shares changed hands, more than five times the recent average volume of trading. NCR's highest close in the last year was Nov. 21, when shares reached $44.58. Teradata accounts for almost a fourth of NCR's annual revenue of more than $6 billion. But when it is split off in six to nine months, analysts said, it is likely to account for more than half the company's value because of its potential to grow faster than the equipment and servicing that NCR will retain.