August begins the historically worst part of the year for stocks. Bank of America says get defensive

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Stocks could be in trouble moving forward as August kicks off a historically tough stretch for the market.

Data compiled by Bank of America showed the S&P 500 has averaged a loss of 0.03% between August and October since 1928, making it the worst three-month period for the broader market index. This period also includes September, a month in which the S&P 500 averages a loss of 1%.

Given this historically weak time period for the market, Bank of America's Stephen Suttmeier thinks this is a good time to "get more defensive."