49%? I couldn't agree more! (3,4)
I believe the answer is:
not half
'i couldn't agree more' is the definition.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for not half that I've seen before include "a less than fair split?" , "To an extreme degree" , "thoroughly" , "a lot" , "in the minority?" .)