Howard Silverblatt, senior index analyst at S&P Dow Jones Indices, said the big caveat to looking at the long-term data in a vacuum is the growing and obvious concern over "COF"—China, oil and the Fed. But he expressed slightly brighter-than-cautious optimism.
"It's not a fun market right now, but the past 23 years has been, and if this is the 'payback' for that—which at this point is a break-even year—sign me up again," said Silverblatt.
There is at least one interesting point of comparison between the current year and past years of weak S&P 500 performance, according to Nicholas Colas, chief market strategist at Convergex.
Both 1984 and 1994 were the start of Federal Reserve rate cycles—1984 was easing and 1994 tightening. (1956 was also the beginning of a Fed rate cycle, though to a less significant degree.)
Read MoreFed rate hike speculation is getting nuts
Colas said in 1994 when he was analyzing autos, the stocks were moving from major leaders to market laggards as the first rate rise loomed. Even though it was somewhat expected, it caught the market by surprise, but the year still ended flat.
"Now it's analogous. The Fed has told us what they would like to do, we just don't know when and the cadence is in question," Colas said. "That creates uncertainty and a flat market, and once uncertainty is past, you get better returns the following year."
He added that the Fed move is not likely to be as severe as it was in 1994.
That year the hike in the fed funds rate was big, starting at 3.05 percent and ending the year at 5.45 percent. "The speed of that move caught the markets by surprise, and this time the Fed has promised to not be as metronomic as during the Greenspan era," Colas said.
Still, Fed uncertainty is a big caveat to set against the data. The market doesn't know the answer yet, and there is no guarantee that once the Fed moves, investors will move on, or more uncertainty follow.