During baseball’s steroids era, it seemed like home run records were broken all the time, CNN Money reported. That’s what the bull market in stocks has felt like the past few years.

The S&P 500 posted 98 record closing highs during 2013 and 2014, according to S&P Dow Jones Indices. And last week, the Nasdaq notched a closing high last seen in March 2000.

But Wall Street records may soon be harder to come by as the Fed-induced “steroids” are taken away.

The extremely low interest rates and quantitative easing provided by the Federal Reserve made stocks look very attractive. Quantitative easing ended last year and interest rates look like they’ll start climbing later this year.

Also, the U.S. economy stumbled at the end of 2014 and the beginning of this year. That has dented corporate profits and hurt stocks.

“It’s harder to hit home runs in October because it’s colder and the air is heavier,” said David Kelly, chief global strategist at JPMorgan Funds. This is clearly not the midsummer for the stock market rally.”