-63.51% is the change from 666 to 243
Calculation steps:
[( 243 - 666 ) ÷ 666] x 100 = -63.51%
Formula
Percentage change = [(243 - 666) / 666] x 100
Subtract the new number by the original number
243 - 666 = -423
-423 ÷ 666 = -0.6351351351351351
-0.6351351351351351 x 100 = -63.51%