How To Plot Volume Bars on Index Charts in Thinkorswim

I’m currently studying William J. O’Neal’s CAN SLIM Investing System.

The M refers to Market Direction. Determining whether the general market is uptrending (bullish) or downtrending (bearish).

O’Neal writes on the importance of monitoring both price and volume changes of markets.

The best way for you to determine the direction of the market is to look carefully at, follow, interpret, and understand the daily charts of the three or four major general market averages and what their price and volume changes are doing on a day-to-day basis.

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Since market indexes are not tradable securities, volume bars will not appear in Thinkorswim for the S&P 500 (SPX) or the NASDAQ-100 (NDX) indexes.

However, using thinkScripts you add lower studies to these charts that plot total NYSE and NASDAQ volume.

SPX NYSE Volume
Plotting NYSE Composite volume as volume bars on the S&P 500 Index (SPX) chart

NYSE Composite Total volume Lower Study thinkScript

declare lower;
plot nyseVolumePlot = close("$TVOLC");
nyseVolumePlot.AssignValueColor(if close-open > 0 then Color.GREEN else Color.RED);

NASDAQ Composite Total volume Lower Study thinkScript

declare lower;
plot nasdaqVolumePlot = close("$TVOLC/Q");
nasdaqVolumePlot.AssignValueColor(if close-open > 0 then Color.GREEN else Color.RED);

These thinkScripts can be modified by changing the technical indicator symbols in the plot line. Visit this page in the Thinkorswim Learning Center for a list of technical indicator symbols that are available.