Excel IF AND statement with percentage output

I have a dataset of co-ordinates, except the co-ordinate is split into two column X and Y.

I'm trying to find the percentage of co-ordinates in a single quadrant, and thought IF/AND statements would work i.e.

IF "numbers in X Column is between -5 and 0" AND "numbers in Y is between -5 and 0" then display total as Percentage of all data
IF "numbers in X Column is between 0 and 5" AND "numbers in Y is between 0 and 5" then display total as Percentage of all data

Etc..

I think that may be the easiest way but I'm stuck on three things;

1. How to do it for negative numbers
2. How to do "is greater than a number BUT less than a number" (rather than just greater/less than), and
3. How to show results as a percentage (I only know how to return a TRUE or FALSE) i.e.:

=IF(AND(A2:A100>5,B2:B100>5),TRUE, FALSE)