Why do low volumes make the stock markets more volatile. http://www.financial-spread-betting.com/Spread-betting-AIM-stocks.html Chris Purdy, Sales Trader at Spreadex. The summer months usually see much lower volumes. On an average day in early August we may only see 750 million shares traded on the FTSE 100. During early March we would see much more trades. During times of low market volumes, individual trades have a bigger impact than normal when under normal conditions it wouldn't move the markets that much.