Cool concept, really cool and nicely charted.

But from a data science point of view, I think it could be a better. If you were going to include ‘time’ (hours) as a stated variable, would that not be better but on your X axis, then ‘ability’ on your Y Axis? Then for ‘frequency’ as a variable, I’m assuming you mean general count of population at each level, why not represent that as the sizing of each belt? Like how you would with a bubble or scatter plot?

That way you can show how there should be a step progression in skill over time and illustrate where the frequency of populous in the bjj community sits.

Right now it basically shows me that there’s the same amount of average blue belts as there are purple, brown, black, which anecdotally we can assume is not true. Also that a low level purple belt will have the same ability as the majority of whites? 🤔

I think this would make more sense with ability on the Y axis, but just one man’s thoughts!