Identify the column by entering SizeQuantity1 in the New Column Name field. From the Operation dropdown, choose Sum. This will generate an error, but we’ll modify the formula directly to correct it.

Learn Excel 365 calculated columns to enhance your data analysis skills with dynamic formulas, cross-table calculations for real-time insight ...

Adding a new column to either an entire spreadsheet or just a portion is an easy thing to do in Microsoft Excel. Here's how.

You can add a column in Excel by right-clicking or using the “Insert” option. These features are helpful for adding new data to a spreadsheet.