The first area chart here at Graphics Ride For Free.
Click the chart to initiate the elargening.
And yes, this did end up being based on feeling as when I tried to do it on ticket sales the numbers weren't that accurately reflective, especially basketball in the 90's and early-mid 2000's where almost every game was a sellout. So this ends up being by far the most obscure chart yet, and that includes trying to chart what being a Sooner fan is all about, so that is saying something.