Investing.com -- A chart highlighted by Sevens Report suggests that U.S. stock market gains in December have typically been driven by strength later in the month rather than early trading. The latest Sevens Report states that December has been “one of the stock market’s best months of the year,” citing data from Carson Group’s Ryan Detrick showing the S&P 500 has averaged a 1.4% return over the past 75 years and finished higher 73.3% of the time. That makes December the month with the highest historical ...