Last year with a query count of just over 13,000, I found that about 18% of papers queried through Lazy Scholar were found freely through Google Scholar.
As of today, the total query count just passed 150,000. Total installations just passed 5,000, and active users measured by Google (however they do this) is nearing 4,000.
Now the proportion of free full texts found through Google Scholar has shot up to 43% (after removing duplicate queries from each user, this left ~80,000 queries). I haven’t scrutinized this data yet so I am not quite sure why it increased so much.
Here are the counts of papers per publication year. As expected, people overwhelmingly are looking for recent papers.
I hope to explore this data in more depth in the near future, so stay tuned. And of course, I have a long list of improvements I hope to make to the extension.