NL winrate formula should contain average stack size AND bb/100?

[laja]

Most players talk about no limit winrates in bb/100 just like in limit, but I think that the formula needs to somehow take into effect the average amount of $ that players have at the table. Like how party has a max buy-in of 50 BB, if that were made bigger or smaller I am sure peoples winrates would be affected even if the blind structure remains the same. Now obviously this shouldn't happen in perfect poker, but this is far from that...