Asian and European equities took a beating today. The Shanghai Composite fell 1%, but the Euro STOXX 50 plunged 3.35%. US equity indexes appeared to be following suit at the open. The S&P 500 did a quick nosedive and hit its -1.53% intraday low less than an hour later. The buyers then returned, and the index advanced with a degree of regularity, breaking into the green early in the final hour of trading. After hitting its 0.24% intraday high, the index closed with a trimmed gain of 0.10%.

The yield on the 10-year note closed the day at 2.14%, down 1 bp from yesterday's close.

Here is a snapshot of past five sessions.

Today's opening selloff dropped the index below its 200-day moving average before the recovery began. Volume on today trade was 19% above its 50-day moving average.

A Perspective on Drawdowns

Here's a snapshot of selloffs since the 2009 trough.

For a longer-term perspective, here is a charts base on daily closes since the all-time high prior to the Great Recession.