Dry Volume

The S&P 500  from the moment of the February sell off to now 

The volume bars below are telling the story of how price and volume were working together from the crest in late-January to the boring period of sideways back and filling, and today's rally attempt.

The high printed at 2878.5 was printed near 1.22 million contracts traded (very low) and then when the sellers began to pick up steam it ballooned into the volume peak at 4.714 million contracts the lowest price points showing where most of the players are trading hands.

One of the other aspects I'd like to point out is the two different directions of the trendlines on the lower volume box where (1) the line slopes down into the "slow period" or 2800 S&P 500 and the other where we begin to see a drop in price followed by stronger uptick in volume

Volume is bored by the lackluster rallies that run out of power; and becoming more excited or shows more confirmation when corrections take a deeper hold.  The coloring of the volume bars matches the daily candlestick so what is most relevant about these two shifts in sentiment are that the peak in volume 4.71m on 2/4 to 2/5 trended down to the tune of 1.67 on 3/1 right before the spike.  Volume then muddled around in the shaded oval before recently picking up again.  The recent gains in volume prints I am noting here are 1.12m to 2.76m in the past 7 trading sessions

Typically speaking we don't take exact measurements and compare absolutely a rate of change in volume (for example) 125.32% increase or decrease of 88.31% we are more concerned with the direction of change and how it looks intuitively, if volume continues to grow along side of the longer length red candlesticks then that could be the very recipe of confirming the duration, magnitude and depth of this correction in the S&P 500.