-34.23% is the change from 999 to 657
Calculation steps:
[( 657 - 999 ) ÷ 999] x 100 = -34.23%
Formula
Percentage change = [(657 - 999) / 999] x 100
Subtract the new number by the original number
657 - 999 = -342
-342 ÷ 999 = -0.34234234234234234
-0.34234234234234234 x 100 = -34.23%