Q1 2018Q4 2017Q3 2017Q2 2017Q1 2017
Gross margin31.8%27.2%33.8%28.4%34.5%
Gross margin growth (bps)-265245-301-509-322
Operating margin-6.1%-10.5%-1.6%-9.0%-4.1%
Operating margin growth (bps)-2001,026-496-484-312
Net profit margin-6.2%-9.6%-1.6%-9.1%-4.2%
Net profit margin growth (bps)-2031,070-492-479-400

Notes:The company changed its fiscal year in 2011 from the end of February to the end of January; therefore, fiscal 2011 only includes 48 weeks of operations and Q4 2011 only includes 9 weeks of operations