The $70 billion Bridgewater All Weather Fund, managed by hedge fund titan Ray Dalio, was down 1.9 percent in September and is down 6 percent through the first nine months of the year, three people familiar with the fund's performance said on Tuesday. The All Weather Fund is one of two big portfolios managed by Bridgewater Associates and uses a so-called "risk parity" strategy that is supposed to make money for investors if bonds or stocks sell off, though not simultaneously. Bridgewater is the latest in a series of alternative asset managers that have struggled to...