A bit confused on something:

Justified forward P/E = D1/E1 / r-g

Trailing P/E = D1/E1 x (1+g) / r-g

Why does trailing include 1+g ? Surely if we are looking at the previous years P/E the payout ratio would have already included the growth rate? Why is Forward not including 1+g if we are looking at future rate?