-23% is the change from 661 to 509
Calculation steps:
[( 509 - 661 ) ÷ 661] x 100 = -23%
Formula
Percentage change = [(509 - 661) / 661] x 100
Subtract the new number by the original number
509 - 661 = -152
-152 ÷ 661 = -0.22995461422087746
-0.22995461422087746 x 100 = -23%