There has never been a time when the PFI went below -20 without a recession. We are not at -30.7! Double dip is just arround the corner.
Seems to depend on the recession, sometimes it bottoms toward the end, sometimes right at the beginning... still very reliable!
What I take away from the chart is that it doesn't predict the beginning of a recession. Rather it predicts the end of a recession or near the end of recession. Recessions have begun when the PFI was above 0. When the PFI reads -30 or -40, it signals the end or near the end of a recession.