Solve for the unknown number of years in each of the following: $($Do not round intermediate calculations and round your answers to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

$\backslash$table$[[$Present Value,Years,Interest Rate,Future Value$],[$$$,10,\%,$$$,1,614],[$$$80,,11,\%,2,058],[830,,16,\%,259,482],[18,600,,13,\%,305,503],[21,700,,,,]]$