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- Open your spreadsheet in Google Sheets
- Select a column by clicking on the gray column cells at the top of the sheet
The column will highlight
- Click on Format
- Find Format in the top menu bar
Additional options will unfold
- Click on Number
A list of data formats will unfold
- Choose the data type Visuals needs for your column
- Learn more at the Visualization Index
Your column will adjust to the correct data type
- Repeat this steps 2-5 for each column