Ann invested $$12000\mathrm{.}00$ of her funds into an account $13$ years ago. During that time, her investment increased $3\mathrm{.}50$ times. What annual rate of return did Ann earn on this investment?

r $=\%$

INSTRUCTIONS: Place your answer in PERCENTAGE form with at least $2$ decimal places. For example, an answer of three and one$-$quarter percent is entered as $3\mathrm{.}25$ and not as $0\mathrm{.}0325.$ ALSO, DO NOT USE A PERCENT SIGN IN YOUR ANSWER. You should work your analysis using at least four decimal places of accuracy.