Competitive analysis for each type up to gen 5
As for how I did this it was as follows: I looked up the tiering placements of one type at a time on Smogon. After this, I assigned every FULLY EVOLVED Pokemon a number based upon what tier it was in, added them all up for that particular type and then found the mean. This was done for all seventeen/fifteen types per generation, and then I ranked them based upon their numbers into what you see now.
Small notes: The general tiering system was
Uber= 5 pts
UU= 3 pts
However I had to change some numbers due to the previous generations not having enough Pokemon/tiers. The lowest number was always 1 and the highest was always 5, so it was still judged fairly despite this.
Also of note: Thanks to R/B not having enough pokemon, there were several ties.