Mickey & Minnie have $$43$ million in cash. Before they retire, they want the $$43$ million to grow to $$92$ million. How many years before Mickey & Minnie can retire if they earn $11\mathrm{.}2\%$ per annum on their stash of cash? Assume annual compounding. $($Enter your answer in years to $2$ decimal places, e$.$g$.,12\mathrm{.}34)$