840.85% is the change from 71 to 668
Calculation steps:
[( 668 - 71 ) ÷ 71] x 100 = 840.85%
Formula
Percentage change = [(668 - 71) / 71] x 100
Subtract the new number by the original number
668 - 71 = 597
597 ÷ 71 = 8.408450704225352
8.408450704225352 x 100 = 840.85%