The salvage value $\backslash ($ S $\backslash )($in dollars$)$ of a company limousine after $\backslash ($ t $\backslash )$ years is estimated to be given by the formula $\backslash ($ S$($t$)=700,000(0\mathrm{.}9)^\{$t$\}\backslash ).$ What is the rate of depreciation $($in dollars per year$)$ after $1$ year? After $10$ years? After $15$ years?

What is the rate of depreciation $($in dollars per year$)$ after $1$ year?

$($Do not round until the final answer. Then round to the nearest hundredth as needed.$)$