Investors are holding their breath as the Dow Jones Industrial Average and the S & P 500 head toward a retest of their 2022 lows this week, the final week of trading for September. September falls in the middle of a seasonally weak period for stocks. By contrast, November and December are typically strong months but — with the market off so much already year to date — the chances of a year-end rally now look less likely, according to Ned Davis Research. "How quickly the economy and earnings decelerate will probably determine whether a year-end rally is possible," said Ed Clissold, Ned Davis' chief U.S. strategist. "Historically speaking, the fact that the market is down year to date makes a year-end rally less likely but not highly improbable." "When the S & P 500 has been up through September, over the last three months of the year it has risen 83.1% of the time by a median of 4.7%," he added. However, "when the S & P 500 has been down through September, it has risen only 54.8% of the time by a median of 2.3%." On the plus side, though, while midterm election years have historically been the weakest, year-end rallies are consistently stronger in those years, Clissold noted. "The low in the autumn of the midterm year to the summer of the preelection year has been the strongest period of the four-year cycle," he said. The S & P 500 temporarily broke below its June closing low of 3,666 Friday and strategists say if it goes below the low again, and stays there, it could signal the next range of targets at 3,400 or below . The broad market index is down 23% this year and more than 7% for the month to date in September. If the losses hold through Friday, that would make the first nine months of this year the worst since 2002 and the fourth worst since 1926, according to Ned Davis.