-33.85% is the change from 647 to 428
Calculation steps:
[( 428 - 647 ) ÷ 647] x 100 = -33.85%
Formula
Percentage change = [(428 - 647) / 647] x 100
Subtract the new number by the original number
428 - 647 = -219
-219 ÷ 647 = -0.3384853168469861
-0.3384853168469861 x 100 = -33.85%