Photos like this show up from time to time:
This one is from a rally last Saturday in Ohio. The article notes that it was held at the same time as a college football game between Ohio State University and the University of Toledo.
Jay Ulfelder and the CrowdCounting Consortium are here to help out.
Trump’s rallies really are shrinking, and by a lot. For those reading quickly (or not at all), I’ll repeat: the numbers in the bar graph are estimated crowd sizes, not numbers of rallies or other variables that might be affected bigly by the fact that this year is not completed yet. I suspect they’ll shrink further as he drops down the Q rabbit hole.