U.S. employers added 18,000 workers in June, less than forecast and the fewest in nine months, while the unemployment rate unexpectedly climbed to 9.2 percent, the highest level this year.   The increase in payrolls followed a 25,000 gain in May that was less than half the rise initially estimated, Labor Department data showed today in Washington. The median estimate in a Bloomberg News survey called for a June gain of 105,000. Lizzie O’Leary reports on Bloomberg Television's "In the Loop."