The 2 year comparison will be filled in when you used TurboTax with the same account for two years in a row. The 2 year comparison can be very helpful to pinpoint items with large changes from the previous year. It will help you to troubleshoot areas of your return that may have discrepancies.
The Tax Cuts and Jobs Act reduced the amount of withholding for many people, so their refunds are lower than in the past.
