| Dependent Variable | Coefficient | Std. Error | p-value |
|---|---|---|---|
| Trend | 0.004 | 0.016 | 0.777 |
| Trend*StoreA | 0.015 | 0.013 | 0.262 |
| Constant | 0.388 | 0.071 | 0.000 |
| R-squared | 0.139 |
Note:The dependent variable is the daily percentage of customers using at least one plastic bag. Results are based on a robust ordinary least squares estimation.