What I actually did in the talk was make a distinction between digital editions and digitized editions (a digitized edition being something like an old print edition accessed through Google Books). Quoting from my talk, “Over 90% of respondents report using digital editions at all, although only just over 40% report using them “more times than I can count”.” To continue, in comparison with this “When asked about digitized editions, however, over 75% report using them “more times than I can count”, and only 2 respondents – .6% – report using them not at all” and “Print edition usage is similar to digitized edition usage, with about 78% reporting they use them “more times than I can count” and no respondents reporting they use them not at all.” So the 90% number for digital editions is the total number of uses (even if the respondent only used a digital edition once), while the numbers for digitized and print editions are actually much higher (100% for print editions and almost 100% for digitized editions) and they used them many more times, too.

I realize now I left out a chart comparing all three, which I’ll put in the talk now. That makes the comparison much more clear. But saying respondents use digital editions 90% and print editions 78% makes it looks like they use digital editions more than print which is not true at all.