That’s because the correlation between crude oil and stocks has not been stable over time. For several decades prior to 2000, for example, that correlation was negative, as you can see in the chart below. During those decades, higher oil prices in a given month led to below-average stock-market returns in the subsequent month.

Several headwinds threaten the U.S. stock market in the near term, but history says the S&P 500 is headed much higher in the long term.

Oil prices slid further and the S&P 500 approached a record on Tuesday after President Trump brokered a shaky cease-fire between Israel and Iran, fueling hopes that the Middle East could avoid a protracted regional war.