Multi-Variable Attribution Analysis

#1
I have a multi-variable equation in which I am trying to run an attribution analysis for the change from one period to another. For example:

Initial Period X*Y+Z = 100

Where X=2 Y=40 Z=20

Second Period X*Y+Z = 125

Where X=4 Y=30 Z=5

Change in value from initial period to second period = 25

Percentage change in value from initial period to second period = 25%

Can you please tell me how I determine the impact each variable had on the increase in value both on an absolute and percentage basis?

Thank you!