-17.93% is the change from 647 to 531
Calculation steps:
[( 531 - 647 ) ÷ 647] x 100 = -17.93%
Formula
Percentage change = [(531 - 647) / 647] x 100
Subtract the new number by the original number
531 - 647 = -116
-116 ÷ 647 = -0.17928902627511592
-0.17928902627511592 x 100 = -17.93%