-77.42% is the change from 310 to 70
Calculation steps:
[( 70 - 310 ) ÷ 310] x 100 = -77.42%
Formula
Percentage change = [(70 - 310) / 310] x 100
Subtract the new number by the original number
70 - 310 = -240
-240 ÷ 310 = -0.7741935483870968
-0.7741935483870968 x 100 = -77.42%