分析门店净销售与贡献毛利。净销售额＝销售毛额－退款；贡献毛利＝净销售额－商品成本，不含租金与人员费用。按门店保留每项输入和计算结果，核对总额，展示差异或结构。输出结果表、图表、Excel 和离线 HTML；不能把相关变化写成因果结论。

Analyze store net sales and contribution. Net sales = gross sales − refunds; contribution = net sales − merchandise costs, excluding rent and staff. Preserve inputs and calculated values by 门店, reconcile totals, and export a table, chart, Excel and offline HTML. Do not infer causation from descriptive changes.