-21.36% is the change from 824 to 648
Calculation steps:
[( 648 - 824 ) ÷ 824] x 100 = -21.36%
Formula
Percentage change = [(648 - 824) / 824] x 100
Subtract the new number by the original number
648 - 824 = -176
-176 ÷ 824 = -0.21359223300970873
-0.21359223300970873 x 100 = -21.36%