Calculating Sales Our little online farmer’s market is growing. Supply can hardly keep up with demand at Charlotte’s Web Site. We're counting the chickens before they are hatched. Is there a way to forecast what we might sell, say Wednesday two weeks from now? Yes, there is. We can set up a spreadsheet that will calculate our sales on any given day. Start Microsoft Excel. When the Welcome screen appears, open a new, blank workbook. What do you see from the top of the screen? Is there a Home Ribbon? And the Insert, Page Layout, Formulas, Data. Review and View Ribbons as well? Yes. Then you are ready to get started.