U.S. stocks have been in a massive bull market for years, but the outlook for future returns looks weak and has been rapidly getting weaker.

According to Morgan Stanley, expectations for future returns are currently at an 11-year low, meaning they’re at their weakest level since before the financial crisis.

This outlook is based on what Morgan Stanley called its “market expectations model for equities,” a new quantitative estimate of the market’s future returns derived from an analysis of earnings expectations.

As of the end of March, the expected return for the S&P 500 SPX, -0.84% is 10.4% over the coming 12 months. While such a gain would undoubtedly be welcomed by investors — such a rally would take the S&P 500 both out of correction territory and back to record levels — Morgan Stanley wrote that this rate of return was the lowest expected rate since January 2007, as well as “below the median since 1986.” (In 2007, stocks hit all-time highs in October before turning sharply lower as the financial crisis began to gain steam.)

Courtesy Morgan Stanley

While some analysts have been sounding the alarm about the outlook for stocks for months — citing equity valuations, changing central bank policy, and signs of slowing global growth, among other factors — Morgan Stanley’s calculated outlook has eroded significantly over the past four months. “Since the end of 2017, market expectations for returns have fallen sharply for U.S. equities,” it wrote.

At the end of last year, a return of 12% was expected, compared with the current view of 10.4%.

Courtesy Morgan Stanley

Separately, a forecast for earnings growth has dropped by 1.6% since the start of the year, from 10.6% to 9.3%, the lowest since February 2015.

The catalyst for this decline was a drop in high-growth earnings forecasts. While the low-growth outlook has been losing steam since March 2017, the high-growth view has dropped sharply thus far in 2018. Morgan Stanley suggested this divergence could be attributed to the tax-reform bill that was passed in December, and when analysts adjusted their expectations for the lower corporate tax rate.

Furthermore, the probability of the low-growth scenario being likely has spiked over the past year, according to Morgan Stanley’s calculation. The odds that the coming market environment will be marked by low growth is currently at 0.6, up from 0.3 at the start of 2016.

While the first-quarter earnings season has largely been strong, with growth coming in at its fastest pace in years, many analysts have warned that the growth may have already peaked.

Read: Why long-term U.S. stock returns look dismal