Pentagon Pattern

Each pentagon grows two more... That raised a lot of questions for me. Like: Is there a rule for how many pentagons at each step? For total number of pentagons after each step? Is there a rule for exposed edges at each step? Total? Is there a rule for number of new vertices at each step? Total? Is there a rule for the number of rhombi at each step? Is there a last step to the pattern? Will the pentagons enclose regular polygons next to the original yellow pentagon?