-8.57% is the change from 70 to 64
Calculation steps:
[( 64 - 70 ) ÷ 70] x 100 = -8.57%
Formula
Percentage change = [(64 - 70) / 70] x 100
Subtract the new number by the original number
64 - 70 = -6
-6 ÷ 70 = -0.08571428571428572
-0.08571428571428572 x 100 = -8.57%