-91.96% is the change from 634 to 51
Calculation steps:
[( 51 - 634 ) ÷ 634] x 100 = -91.96%
Formula
Percentage change = [(51 - 634) / 634] x 100
Subtract the new number by the original number
51 - 634 = -583
-583 ÷ 634 = -0.919558359621451
-0.919558359621451 x 100 = -91.96%