You are pasting a new data series, which will affect the existing information along the category axis in your chart. You ...

You are pasting a new data series, which will affect the existing information along the category axis in your chart. You can either replace the existing data categories or add new categories to the existing categories in your chart. What do you want to do?  • To permanently replace the existing categories with categories based on the new data series, click OK. • To add new categories based on the data series but still keep the existing categories in the chart, click Cancel.