Given that ultimate volumes aren't relevant, I think a stacked line chart (with colours for each language) might be appropriate. You might need to bunch togethe

Given that ultimate volumes aren't relevant, I think a stacked line chart (with colours for each language) might be appropriate. You might need to bunch together the least popular languages as "other" to get that to work though. What struck me however was how little the popularity of the largest languages changed in terms of their question frequency.