NEW YORK (Bloomberg) — Residential construction in the U.S. unexpectedly dropped in October amid concern a homebuyer tax credit would expire, illustrating the market's dependence on government help to sustain a recovery as job losses mount. Builders broke ground on 529,000 houses at an annual pace, down 11 percent from the prior month and the fewest since April's record low, Commerce Department figures showed today in Washington. Data from the Labor Department signalled inflation will be of little concern for the Federal Reserve. Homebuilding seized up as builders waited for President Barack Obama to extend a first-time buyer incentive, which has since been passed.