There is not one answer here -- there are at least 4 or more.

Are we talking about the change when I recline my seat or when the individual in front of me reclines?

Are we talking about a pivot / hinged seat back or slider seat?
Note on the pivot / hinged seat, the among of recline varies across the fleet and the height location of the pivot / hinge also varies.

Also in many aircraft E+ has more recline than does E--

so at a minimum there are 4 answers and in reality, there are more than 4. Probably at least 2 more and maybe 4 or 6 more.

And this assumes we are only discussing economy.