Suspendus Company has the following financial data for the year ended December 31, 2021: net sales $1,680,000, operating expenses $880,000, net income $104,000, stockholders’ equity $800,000, and assets $1,901,000. The information for the year ended December 31, 2020 was: net sales $1,450,000, operating expenses $760,000, net income $87,000, stockholders’ equity $700,000, and assets $1,601,000. Calculate the gross profit margin for the year ended December 31, 2021.