-17.8% is the change from 191 to 157
Calculation steps:
[( 157 - 191 ) ÷ 191] x 100 = -17.8%
Formula
Percentage change = [(157 - 191) / 191] x 100
Subtract the new number by the original number
157 - 191 = -34
-34 ÷ 191 = -0.17801047120418848
-0.17801047120418848 x 100 = -17.8%