821.43% is the change from 70 to 645
Calculation steps:
[( 645 - 70 ) ÷ 70] x 100 = 821.43%
Formula
Percentage change = [(645 - 70) / 70] x 100
Subtract the new number by the original number
645 - 70 = 575
575 ÷ 70 = 8.214285714285714
8.214285714285714 x 100 = 821.43%