$4$ years ago, you invested $$29,000.$ In $4$ years, you expect to have $$41,717.$ If you expect to earn the same annual return after $4$ years from today as the annual return implied from the past and expected values given in the problem, then in how many years from today do you expect to have $$47,271?$

Input instructions: Round your answer to $2$ decimal places. $$

years