-54.2% is the change from 666 to 305
Calculation steps:
[( 305 - 666 ) ÷ 666] x 100 = -54.2%
Formula
Percentage change = [(305 - 666) / 666] x 100
Subtract the new number by the original number
305 - 666 = -361
-361 ÷ 666 = -0.5420420420420421
-0.5420420420420421 x 100 = -54.2%