-50.23% is the change from 661 to 329
Calculation steps:
[( 329 - 661 ) ÷ 661] x 100 = -50.23%
Formula
Percentage change = [(329 - 661) / 661] x 100
Subtract the new number by the original number
329 - 661 = -332
-332 ÷ 661 = -0.5022692889561271
-0.5022692889561271 x 100 = -50.23%