Peterson, Howell & Heather Inc., Baltimore-based fleet management firm has come up with some inter­esting figures on gasoline mileage for fleet cars.

According to the company, the typical fleet car to­day is averaging 14.6 miles per gallon of gasoline, compared with 14.4 miles per gallon in 1958 and 14.3 m.p.g. in 1959.

The figures are for standard sized eight cylinder sedans equipped with an automatic transmission and are based on an annual mileage of 25,000 miles.

While the increase in mileage may seem slight, it is significant when considering that today's standard car is heavier than 1958 and 1959 models and is usually loaded down with power-draining accessories.

David N. W. Grant Jr., PHH vice president and director of expense control, said that extravagant mile­age claims for compact cars are not generally realized although as a class, the compacts do give better gaso­line economy.

"The range is wide, just as might be expected when the auto industry itself cannot agree on just what is and what is not a compact," Grant said.

Grant said that a six cylinder car equipped with a manual transmission will average approximately 1.5 miles per gallon more than an eight cylinder car with an automatic transmission. However, because of the added convenience, eight cylinder cars with automatic transmissions are more popular fleet cars. A sedan will average 0.9 more per gallon than a station wagon while air conditioning will reduce mileage by 0.6 of a mile, Grant said.

Peterson, Howell & Heather recommends that its clients use regular grade gasoline rather than premium because "today's engines are designed to give top per­formance with gasoline which sells about: 3 cents per gallon under premium prices."

"With a controlled cost per gallon, with better built-in engine economy and with sensible driving habits on the part of its salesmen, a company can't help but see the magic cost-per-mile figure take a comfortable drop," the company said.

The company said that the average per mile cost of gasoline today is 2.16 cents compared with 2.1S cents four years ago "despite changes in cars and equipment and a continuing upward trend in federal and state taxes boosting the cost at the pump."