August trading volume has been the lightest it’s been in three years, so enjoy the quiet while it lasts because after Labor Day a host of catalysts await traders returning from vacations that could rock the market and boost volumes considerably. Over the past two weeks, trading volume has slowed to a crawl, falling below even seasonally low August averages, culminating last Friday with the lightest session of full-day trading of the year, at 4.81 billion shares. While August may be experiencing the “traders on vacation in the Hamptons” effect, there are a number of uncertainties on the horizon that are playing into the light trading.via