-98.7% is the change from 770 to 10
Calculation steps:
[( 10 - 770 ) ÷ 770] x 100 = -98.7%
Formula
Percentage change = [(10 - 770) / 770] x 100
Subtract the new number by the original number
10 - 770 = -760
-760 ÷ 770 = -0.987012987012987
-0.987012987012987 x 100 = -98.7%