The probability distribution for a discrete random variable $X$ is given below. $$\begin{array}{|c|c|c|c|c|} \hline X & 1 & 2 & 3 & 4 \\ \hline P(X) & 0.3 & 0.4 & 0.2 & 0.1 \\ \hline \end{array}$$The expectation value of $X$ is (up to one decimal place) _____________