E17.9. The Quality of Gross Margins: Vitesse Semiconductor Corp. (Easy) Vitesse Semiconductor reported the following revenues and cost of goods sold for 2001-2003 (in thousands): 2003 2002 2001 Revenues $156,371 $151,738 $383,905 Cost of revenues 73,163 110,155 201,536 Calculate the gross margin ratio (gross margin/sales) for each year. In 2001 the firm took a charge for obsolete inventory of $46.5 million and, in 2002, another $30.5 million. Explain how these charges affect the gross margin ratio in each of the three years.