When it comes to creating pie charts in Excel, there are a few things to keep in mind in order to avoid negative values. First and foremost, make sure that the data you're using to create the pie chart is free of any negative values. If there are any negative values present, they will need to be converted to positive values before proceeding. To do this, simply take the absolute value of each negative number.
Once your data is ready, you'll need to select it and then click the "Insert" tab on the ribbon. From here, click "Chart" and then choose "Pie" from the list of available chart types. Excel will then insert a blank pie chart into your worksheet.
Next, you'll need to add your data to the chart. To do this, click on the chart and then click the "Data" tab on the ribbon. From here, click "Select Data" and then click "Add." In the "Series Values" field, enter your data range (which should now only contain positive values) and then click "OK."
Your pie chart should now be populated with your data! If you want to change the appearance of your chart, there are a number of options available under the "Design" tab on the ribbon. For example, you can change the color scheme or add labels to your pie slices. Experiment with different options until you find something that looks good.