**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!