-91.62% is the change from 668 to 56
Calculation steps:
[( 56 - 668 ) ÷ 668] x 100 = -91.62%
Formula
Percentage change = [(56 - 668) / 668] x 100
Subtract the new number by the original number
56 - 668 = -612
-612 ÷ 668 = -0.9161676646706587
-0.9161676646706587 x 100 = -91.62%