A $16$-bit synchronous binary up-counter is clocked with a frequency $f_{\text{CLK}}$.The two most significant bits are $\text{OR-ed}$ together to form an output $Y$. Measurements show that $Y$ is periodic, and the duration for which $Y$ remains high in each period is $\text{24 ms}$. The clock frequency $f_{\text{CLK}}$ is ____________$\text{MHz}.$ (Round off to $2$ decimal places.)