Lattice Radiant: What does DOPAD_DEL on Timing analyzer report means?

Lattice Radiant: What does DOPAD_DEL on Timing analyzer report means?

The DOPAD_DEL is the delay from the PADDO port to the IOPAD signal switching rail to rail and measured at mid point. 
It is dependent on several factors such as :
1. The drive strength : 8ma default
2. The slew rate.

Note: As #1 and #2 increases, the delay decreases.