-50.41% is the change from 851 to 422
Calculation steps:
[( 422 - 851 ) ÷ 851] x 100 = -50.41%
Formula
Percentage change = [(422 - 851) / 851] x 100
Subtract the new number by the original number
422 - 851 = -429
-429 ÷ 851 = -0.5041128084606346
-0.5041128084606346 x 100 = -50.41%