-92.12% is the change from 647 to 51
Calculation steps:
[( 51 - 647 ) ÷ 647] x 100 = -92.12%
Formula
Percentage change = [(51 - 647) / 647] x 100
Subtract the new number by the original number
51 - 647 = -596
-596 ÷ 647 = -0.9211746522411128
-0.9211746522411128 x 100 = -92.12%