Speculators reduced favourable bets on the US dollar for a third straight week, paring net longs to their smallest in five weeks, as investors were doubtful the Federal Reserve would raise rates this year. The value of the dollar's net long position fell to $9.81 billion in the week ended August 16, from 11.41 billion the previous week, according to Reuters calculations and data from the Commodity Futures Trading Commission released on Friday. Sterling net short positions soared to 94,238 contracts, a record high, the data showed.