-9.05% is the change from 210 to 191
Calculation steps:
[( 191 - 210 ) ÷ 210] x 100 = -9.05%
Formula
Percentage change = [(191 - 210) / 210] x 100
Subtract the new number by the original number
191 - 210 = -19
-19 ÷ 210 = -0.09047619047619047
-0.09047619047619047 x 100 = -9.05%