-81.09% is the change from 645 to 122
Calculation steps:
[( 122 - 645 ) ÷ 645] x 100 = -81.09%
Formula
Percentage change = [(122 - 645) / 645] x 100
Subtract the new number by the original number
122 - 645 = -523
-523 ÷ 645 = -0.8108527131782945
-0.8108527131782945 x 100 = -81.09%