-34.62% is the change from 78 to 51
Calculation steps:
[( 51 - 78 ) ÷ 78] x 100 = -34.62%
Formula
Percentage change = [(51 - 78) / 78] x 100
Subtract the new number by the original number
51 - 78 = -27
-27 ÷ 78 = -0.34615384615384615
-0.34615384615384615 x 100 = -34.62%