-92.27% is the change from 660 to 51
Calculation steps:
[( 51 - 660 ) ÷ 660] x 100 = -92.27%
Formula
Percentage change = [(51 - 660) / 660] x 100
Subtract the new number by the original number
51 - 660 = -609
-609 ÷ 660 = -0.9227272727272727
-0.9227272727272727 x 100 = -92.27%