Problem $4-7$ Calculating Sustainable Growth $[$LO$3]$

Assets and costs are proportional to sales. Debt and equity are not. The company maintains a constant $40$ percent dividend payout ratio. What is the sustainable growth rate? $($Do not round intermediate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

Sustainable growth rate

$\%$