AP
This is the second time in the last six months that this has happened - remember, stocks fell 10% back in August in just a few days - and these two corrections in such a short period of time don't look good, historically.
Any single correction isn't, in and of itself, a problem, but the speed with which stocks dropped into correction territory almost back-to-back has only been seen three other times in the last 100 years.
And these are not years market historians want to hear: 1929, 2000, and 2008.
In an afternoon email on Wednesday, Rich Barry, floor governor at the NYSE - citing commentary from floor legend Art Cashin - wrote:
"Allow me to cut and paste an interesting and ominous piece from Arthur's morning comments: 'Jason Goepfert, the outstanding pilot of SentimenTrader dug into his incredibly extensive files to uncover a rather rare condition. He noted that the indices have had two 10% corrections in a rather short span. That has only happened three times in the last 100 years. Unfortunately, those occurrences were in 1929, 2000 and 2008. As you may recall, those were not particularly good years for the bulls.' Oh boy. Perhaps this time will be different."
Oof.
For less historically-inclined readers, each of these years saw major market crashes, one of which led to the Great Depression, one of which led to the Great Recession, and another that saw the air come out of the tech bubble that ushered in a new millennium.
The S&P 500 fell more than 10% in each of these years and dropped 38% in 2008 alone. The 2000 and 1929 events were followed by more brutal years.
On Thursday stocks were ripping higher but the topsy-turvy action seen in markets this year is what really has markets on edge and Thursday's rally probably isn't putting many investors at ease.