-87.17% is the change from 647 to 83
Calculation steps:
[( 83 - 647 ) ÷ 647] x 100 = -87.17%
Formula
Percentage change = [(83 - 647) / 647] x 100
Subtract the new number by the original number
83 - 647 = -564
-564 ÷ 647 = -0.8717156105100463
-0.8717156105100463 x 100 = -87.17%