-18.21% is the change from 939 to 768
Calculation steps:
[( 768 - 939 ) ÷ 939] x 100 = -18.21%
Formula
Percentage change = [(768 - 939) / 939] x 100
Subtract the new number by the original number
768 - 939 = -171
-171 ÷ 939 = -0.18210862619808307
-0.18210862619808307 x 100 = -18.21%