Hydrogen iodide decomposes through the reaction $2HI\leftrightharpoons H_{_{2}}+I_{2}$. The value of the universal gas constant $R$ is $8.314 \:J\:mol^{-1}K^{-1}$. The activation energy for the forward reaction is $184000\:J\:mol^{-1}$.  The ratio (rounded off to the first decimal place) of the forward reaction rate at $600 \:K$ to that at $550\:K$ is ________