How much did Peter Jackson take out of the books for the films?

Question

just a rough percentage. thanks.

Answer 1

I would estimate approximately 15%.  

Answer 2

The reason it made so much money was because Jackson kept a lot of the original material.

Fellowship, I'd say somewhere between 85-95%.

Two Towers, was a little less, I'd say 80-90%.

Return of the King, I'd say 90-95%.

Hope it helps.