Rating: Online correspondence mode vs online blitz mode

I am interested in comparing the chesscom online rating of the players around here. I want to hear from the active players. You could be the one posting here..

a) online correspondence: by this i mean - you are taking the game seriously, and really putting an effort to make the best of your ability...and you get a rating.

b) online blitz: you are probably playing a lot of online games at a time, and usually blitzing out moves, occasionally stopping for a moment in a critical position once in a while..and you get a rating..

obviously the two ratings for the same player should be different..

by how much they should differ? for me i guess it is about a class apart (~200 - 300 rating points)

share your experence, if you have any..