Found this on Deviantart:
"I did it for fifth generation on my journal, now I present to you a bunch of incoherent squiggles that more or less accurately tell you the best viable types per generation. Note that these data only give a representation of the best OVERALL types per generation- not specific Pokemon.
Some interesting points:
Type that changed the most: Fighting from 2nd to 3rd gen, moving up 11 places.
Type that changed the least: Dragon and Normal from 3rd to 5th generation.
Type that rose the most from 2nd to 5th gen: Fighting, which went up 14 places.
Type that fell the most from 2nd to 5th gen: Rock, which went down 5 places.
Most consistent: Steel.
Most erratic: Fighting.
Overall Best (2nd gen ->): Dragon, then Steel, then Psychic
Overall Worst (2nd gen ->): Normal, then Bug, then Poison
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
OU= 4pts
BL= 3.5pts
UU= 3 pts
RU= 2pts
BL2= 1.5pts
NU= 1pt
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."
Make of it what you will.
