Relative volume gives us a clue as to the participation of large, institutional traders in the current market. It also correlates highly with intraday volatility, thus providing clues as to whether or not we'll be able to hit particular profit targets.
Here are median five-day ES volume numbers for each 15-minute period during the day that I use in my trading. All times are Central Time:
8:30 AM - 151,383
8:45 AM - 132,213
9:00 AM - 149,659
9:15 AM - 114,851
9:30 AM - 98,618
9:45 AM - 90,566
10:00 AM - 142,282
10:15 AM - 72,932
10:30 AM - 58,067
10:45 AM - 53,210
11:00 AM - 52,965
11:15 AM - 57,078
11:30 AM - 33,053
11:45 AM - 47,135
12 N - 40,629
12:15 PM - 47,346
12:30 PM - 41,972
12:45 PM - 31,933
1:00 PM - 47,043
1:15 PM - 38,975
1:30 PM - 50,185
1:45 PM - 55,170
2:00 PM - 48,564
2:15 PM - 73,848
2:30 PM - 79,974
2:45 PM - 135,342
3:00 PM - 150,838
8:45 AM - 132,213
9:00 AM - 149,659
9:15 AM - 114,851
9:30 AM - 98,618
9:45 AM - 90,566
10:00 AM - 142,282
10:15 AM - 72,932
10:30 AM - 58,067
10:45 AM - 53,210
11:00 AM - 52,965
11:15 AM - 57,078
11:30 AM - 33,053
11:45 AM - 47,135
12 N - 40,629
12:15 PM - 47,346
12:30 PM - 41,972
12:45 PM - 31,933
1:00 PM - 47,043
1:15 PM - 38,975
1:30 PM - 50,185
1:45 PM - 55,170
2:00 PM - 48,564
2:15 PM - 73,848
2:30 PM - 79,974
2:45 PM - 135,342
3:00 PM - 150,838
Note how volume shifts during the day (the well-known "smile" pattern), with institutions most active early and late in the day. The 10 AM bulge represents activity due to economic releases at that time. Expectable volume would be more like 80,000 for days without releases.
With these numbers, you can make a reasonable estimate of whether markets are likely to be volatile or quiet during the trading day; you can also observe where volume picks up and tails off: nice clues as to the market's auction activity.
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