Make sure data is in the correct format. To help Visuals understand your spreadsheet, use a specific data type for each column. If you're not sure which data type your columns need, check out the Visualization Index.  

  1. Open your spreadsheet in Google Sheets
  2. Select a column by clicking on the gray column cells at the top of the sheet
  3. Click on Format
  4. Click on Number
  5. Choose the data type Visuals needs for your column
  6. Repeat steps 2-5 for each column