-91.63% is the change from 215 to 18
Calculation steps:
[( 18 - 215 ) ÷ 215] x 100 = -91.63%
Formula
Percentage change = [(18 - 215) / 215] x 100
Subtract the new number by the original number
18 - 215 = -197
-197 ÷ 215 = -0.9162790697674419
-0.9162790697674419 x 100 = -91.63%