It would be really helpful if you could show your work: I struggle with this concept. Thank you. :)

Under Armour, Inc. is an American supplier of sportswear and casual apparel. Following are selected financial data for the company for the period 2009-2013. Profit margin (%) Retention ratio (%) Asset turnover (X) Financial leverage (X) Growth rate in sales (%) 2009 5.7 100.0 1.8 1.9 19.5 2010 6.6 100.0 1.8 1.9 25.6 2011 6.8 100.0 1.8 2.1 39.8 2012 7.2 100.0 1.8 2.0 26.0 2013 7.2 100.0 1.7 2.1 28.5 a. Calculate Under Armour's annual sustainable growth rate for the years 2009 through 2013. (Round your answers to 1 decimal place.) Year 2009 2010 2011 2012 Sustainable Growth Rate % % % % 2013 %