I cannot map the numbers shown in the graph with the numbers seen in the page following the link. However, the graph seems to be counting number of contributions. Wouldn't it be more useful to count number of developers?
FICTIONAL EXAMPLE: If 2 developers contribute 10 patches each to Wikipedia Android app and 10 developers contribute 2 patches each to MediaWiki Core, both make a total of 20 patches, but it is a lot more interesting to see that MediaWiki Core got 10 newcomers.
Focusing on people rather than patches also diminishes the problem of comparing patches by complexity. Instead, the complexity of attracting a new developer is quite comparable across people and projects.