This is from a Trade Alert presentation at a SIFMA conference in 2017. 23% is SPY or SPX - over 70% of the volume is clustered in the top 25 names.
That's basically just a graphical representation of Barchart's list of Most Active ETF, and Index, and Stock options. https://www.barchart.com/options/most-active/etfs SPY, S&P 500 ETF, is always the monster in options volume, by-far. SPX index is a fraction of its volume. and individual Stocks are a further tiny fraction.
Not to be a stinker, but somebody didn't proof. As a pie chart, over one-quarter of the area is SPY -- maybe 26%-27% -- not the 16% that the graphic claims. If you give it a tilt, you can imagine the SPX to be about half of a quarter -- or 12.5% or so -- not the 7% claimed. And of course, when you add the two areas together, you have something approaching 40% -- or about 26.5% + 12.5% = 39% As these things go, graphs usually come from data, and labels from a human input -- but both of these appear data driven. Either way, somet'ing screwed here, mon.
remember FREE THE SPX!? I have the buttons and hats. Then again I have an entire sleeve of the DJX opening day green hats.