According to Matthew Hilger's book Internet texas Holdem the cutoff line between a loose and a tight table is 30% Higher than that it's a loose table, lower than that it's tight. I like that cutoff line and it makes sense, but what average pot size or PFR% would be considered a passive table?

I have been trying looser tables with mixed results, but I am never sure where I should draw the line as to whether a table is passive or aggressive. I play .50/$1 so if your answer isaverage pot size, would $5 and above average pot size would be the line to use then that would be a pot size of 5 big bets. Seems a little low, but I remember reading an article somewhere that said look for pot sizes between 5-7 big bets. If it is PFR% as kept tract by the game time tab in Poker Tracker would a table average of 7% PFR be a cutoff to use? All opinions welcome.