In an $\mathrm{n}-\mathrm{p}-\mathrm{n}$ common emitter (CE) transistor the collector current changes from 5 mA to 16 mA for the change in base current from $100 \mu \mathrm{~A}$ and $200 \mu \mathrm{~A}$, respectively. The current gain of transistor is $\_\_\_\_$ .
