WASHINGTON (AP) — The number of Americans signing contracts to buy homes fell slightly in October as tight credit and lagging wages remained financial hurdles for would-be homebuyers.The National Association of Realtors said Wednesday its seasonally adjusted pending home sales index fell 1.1 percent in the past month to 104.1. The index remains below its 2013 average but is 2.2 percent higher than last October.Pending sales are a barometer of future purchases. A one- to two-month lag usually exists between a contract and a completed sale. The number of contract signings rose in the Northeast but fell in the Midwest, South and Western regions of the U.S.Pantheon Macroeconomics’ Ian Sheperdson said the latest numbers are “more evidence that the trend in housing market activity is flat, despite the gains in existing home sales in the past couple of months.”Sales of existing homes rose 1.5 percent to 5.26 million last month, the briskest pace this year.