While making the Photo Collage I checked everyone's profile (for registration date and post count) and also noted their member number (which you can trace from the URL). Then I came up to an idea. 
I made a chart with the date on the X-axis and the member number on the Y-axis and plotted every recorded member on this. As a result you can see how many people have registrated in total at a certain time.
Pretty cool, huh?

I made a chart with the date on the X-axis and the member number on the Y-axis and plotted every recorded member on this. As a result you can see how many people have registrated in total at a certain time.

