-87.7% is the change from 634 to 78
Calculation steps:
[( 78 - 634 ) ÷ 634] x 100 = -87.7%
Formula
Percentage change = [(78 - 634) / 634] x 100
Subtract the new number by the original number
78 - 634 = -556
-556 ÷ 634 = -0.8769716088328076
-0.8769716088328076 x 100 = -87.7%