The stock market is forward-looking. That’s a problem when there’s not much to look forward to.

Stocks sank for the fourth-straight day on Tuesday, as investors looked past a series of outwardly positive earnings reports and fixated on threats to the nine-year-old bull market.

Foremost among them is the Federal Reserve. Super-low interest rates from the central bank have fueled the rally, pushing up the prices of stocks and bonds since the Great Recession.

But that was then. Now, the Fed is slowly withdrawing some of its support. It is shrinking its portfolio of government bonds and lifting interest rates. As a result, a yearslong tailwind for the stock market is disappearing.

The new environment is evident in interest rates on government bonds, closely watched by many investors. The yield on the 10-year Treasury note touched 3 percent in trading early Tuesday. That benchmark interest rate — which influences the price of borrowing for both consumer loans and corporate bonds — has not been that high since early 2014.