-67.42% is the change from 666 to 217
Calculation steps:
[( 217 - 666 ) ÷ 666] x 100 = -67.42%
Formula
Percentage change = [(217 - 666) / 666] x 100
Subtract the new number by the original number
217 - 666 = -449
-449 ÷ 666 = -0.6741741741741741
-0.6741741741741741 x 100 = -67.42%