1 Avis Inc., following rival Hertz Corp. 's lead, said it is backing out of frequent-flier programs with three airlines.
2 The Garden City, N.Y., car-rental company said it won't renew contracts with NWA Inc. 's Northwest Airlines unit, Pan Am Corp. 's Pan American World Airways unit and Midway Airlines at the end of this year.
3 But it remains involved in programs with AMR Corp. 's American Airlines unit and Delta Air Lines.
4 Industry estimates put Avis's annual cost of all five programs at between $8 million and $14 million.
5 A spokesman for Avis wouldn't specify the costs but said the three airlines being dropped account for 'far less than half' of the total.
6 Budget Rent a Car Corp., of Chicago, and National Car Rental Systems Inc., of Minneapolis, both said they had no plans to follow suit.
7 In fact, Budget indicated it saw some benefit to staying involved in these programs, in which renters earn frequent-flier miles and fliers can get car-rental discounts.
8 'I cannot see how this news by Hertz and Avis cannot benefit Budget's programs,' said Bob Wilson, Budget's vice president, marketing planning.
9 Northwest and Midway are two of the five airlines with which Budget has agreements.
10 National also participates in the Northwest frequent-flier program along with four other airlines, including Delta and USAir Group Inc. 's USAir unit.
11 A month ago, Hertz, of Park Ridge, N.J., said that it would drop its marketing agreements at year end with Delta, America West and Texas Air Corp. 's Continental Airlines and Eastern Airlines, and that pacts with American Airlines, UAL Inc's United Airlines and USAir also would be ended. . . sometime after Dec. 31.
12 At the time, Hertz said its annual fees to those airlines amounted to $20 million and that the value of redeemed awards topped $15 million.
13 Analysts and competitors, however, doubt the numbers were that high.
14 Budget said its frequent-flier costs are 'substantially below' Avis's level.
15 Robert D. Cardillo, Avis vice president of marketing, said, 'The proliferation and costs attached to {frequent-flier programs} have significantly diminished their value.'
16 This year has been difficult for both Hertz and Avis, said Charles Finnie, car-rental industry analyst at Alex.
17 Brown & Sons. 'They've been looking to get their costs down, and this is a fairly sensible way to do it,' he said.

A spokesman for Avis wouldn ' t specify the costs but said the three airlines being dropped account for " far less than half " of the total .
wouldn ' t specify the costs
why wouldnt he specify?