-92.49% is the change from 666 to 50
Calculation steps:
[( 50 - 666 ) ÷ 666] x 100 = -92.49%
Formula
Percentage change = [(50 - 666) / 666] x 100
Subtract the new number by the original number
50 - 666 = -616
-616 ÷ 666 = -0.924924924924925
-0.924924924924925 x 100 = -92.49%