KEY POINTS
  • Wall Street analysts are already slashing their earnings growth estimate for 2019 to only single digits, according to FactSet.
  • Economist Ed Yardeni curbs his enthusiasm for the earnings outlook, projecting growth of just 5 percent next year.
  • The S&P 500 has fallen 12 percent in the past three months, wiping out its gains in 2018.
Traders work on the floor of the New York Stock Exchange (NYSE) in New York.

No matter what you believe is driving the stock market in the short term — the Federal Reserve, a trade war, Trump's Twitter — the value of stock prices over time ultimately will come down to earnings.

And that means the future is only getting bleaker from here.