Depends

The larger the value of (E + P) / N then the more complex the directed graph is, where
The value of (E + P  N) / N varies between 0 and N. A stricly layered architecture will have a value of 0.
The sum of (E + P  N) is 2, sum of (E + P  N) / N is 0.22.
Section  N  E + P  N  (E + P  N) / N 

Plugins  9  2  0.22 
Top level  5  0  0.00 
Common  3  0  0.00 
Plugins::language  3  0  0.00 