The Dow Jones industrial average and the S&P 500 posted gains for the fifth straight week on Friday after President Donald Trump signed a bill that revamps the U.S. tax code.
The major indexes closed slightly lower for the day on Friday, however.
Trump signed a bill on Friday that slashes the corporate tax rate to 21 percent from 35 percent. The president was able to sign the bill after Congress approved another bill to keep the federal government funded through Jan. 19.
Investors have been eagerly awaiting this, as they bet that lower taxes will boost companies' bottom lines.
Ben Snider, a strategist at Goldman Sachs, said in a note Thursday, said he expects the tax bill to lift S&P 500 earnings by 5 percent.
"Although we believe that US equities have broadly priced the passage of tax reform, considerable uncertainty remains," Snider said. "In particular, investors still lack visibility into the impact of specific provisions at the company level and how corporate behavior will respond to the new tax code and the incremental cash flows it creates. This uncertainty and shifts in positioning suggest that opportunities still exist – particularly at the micro level – as the market digests the implications of tax reform."