The S&P 500 index is off to its worst start to a year since the Covid-19 fuelled selloff in March 2020. The U.S. Federal Reserve is also set to hike rates this week. Historically, U.S. stocks experience volatility after a rise in rates. But the bull run may not be over going by historical experience. In the previous eight hiking cycles, S&P 500 rose a year after the first increase every time.