-91.04% is the change from 670 to 60
Calculation steps:
[( 60 - 670 ) ÷ 670] x 100 = -91.04%
Formula
Percentage change = [(60 - 670) / 670] x 100
Subtract the new number by the original number
60 - 670 = -610
-610 ÷ 670 = -0.9104477611940298
-0.9104477611940298 x 100 = -91.04%