-9.55% is the change from 670 to 606
Calculation steps:
[( 606 - 670 ) ÷ 670] x 100 = -9.55%
Formula
Percentage change = [(606 - 670) / 670] x 100
Subtract the new number by the original number
606 - 670 = -64
-64 ÷ 670 = -0.0955223880597015
-0.0955223880597015 x 100 = -9.55%