428149 (29) [Avatar] Offline
The point that PageRank is affected by the speed of loading is worth making. However, this bar chart doesn't do that. PR depends on a variety of factors, so it's not meaningful to compare the PRs of different pages and compare them with the loading times. Maybe some pages load faster because they have less content and therefore fewer back-links (and hence lower PR). Who knows?

In any case, according to your data, PR actually drops as the time taken to load the page increases.
Perhaps if you had included a wider range of speeds, mentioned how many pages you measured and then done a simple statistical analysis you could have demonstrated that there is a significant correlation. As it stands, the bar chart is meaningless.

I don't actually think that it's even necessary to prove this point, since Google has told us that it uses loading speed in its algorithm. It might be worth explaining how it does this, rather than attempting to prove something which isn't in dispute.