The Office for National Statistics in Britain said the annual inflation rate, helped by lower transportation costs, dropped from March to April to 2.4 percent. The inflation rate fell from 2.8 percent in the previous month with notable declines in the price of gasoline and air fares, ONS said. April marked the first time since August that the rate of inflation was down. For six months the rate had been \"particularly stable,\" ONS said. Prices for shelter, established in the Consumer Price Index for Housing, rose 2.2 percent in the month at an annual rated, down from 2.6 percent in March.