___Natural gas vehicles making inroads; sales rising DETROIT (AP) â¿¿ Ford Motor Co. said Tuesday it sold a record 11,600 natural gas vehicles last year, more than four times the number it sold two years ago. It's the latest sign that natural gas is making inroads as a transportation fuel, particularly for truck fleets, buses and taxis. The consumer market is tougher to crack, but sales are gaining there as well. Natural gas is cheap and plentiful in the U.S. after a spike in production that began in the middle of last decade. At the same time, the price of gasoline and diesel fuel has jumped more than 30 percent. That makes natural gas â¿¿ which also emits fewer greenhouse gases â¿¿ an increasingly attractive option for truck companies and municipalities. But while natural gas may be a good choice for snow plows and trash trucks, which go relatively short distances and can refuel at city-owned pumps, it's a tougher call for ordinary consumers. Natural gas cars cost more and there are few public places to refuel them. Those issues need to be addressed if the vehicles are to significantly boost their share of the auto market, which is currently less than 1 percent. ___ US service firms grows at fastest pace in a year WASHINGTON (AP) â¿¿ U.S. service companies grew in February at the fastest pace in a year, buoyed by higher sales, more new orders and solid job growth. The gain suggests higher taxes have yet to slow consumer spending on services. The Institute for Supply Management said Tuesday that its index of non-manufacturing activity rose to 56 in February from 55.2 in January. Any reading above 50 indicates expansion. The report measures growth in industries that cover 90 percent of the work force, including retail, construction, health care and financial services. A solid recovery in the housing market helped drive the index higher.