How does it work?
The date modifier shifts the formula's focus to another date field. Say you created 10 registrations last week and updated 3 of them today. A widget with time period Today can display either 0 or 3, depending on the date field the formula considers.
The modifier will only take effect in your formula component. It will not change the default date field of your data source.
To add a date modifier:
Click the three little dots in the top-right of your Data function component, then choose another Date field.