A parallel plate capacitive displacement sensor has a plate area of \(2\ \text{cm}^2\). The air gap between the plates is decreased by \(0.1\) mm from an initial value of \(0.5\) mm. The percentage change in the capacitance value is __________ %.
(Assume permittivity as \(\epsilon_0 = 8.854 \times 10^{-12}\ \text{F/m}\))