How can I automatically capture date of entry on form

Hello - I've setup a webform for users to enter information about potential participants in a program. I want the form to automatically capture the date when the form is completed. I had initially set it up where I established a date field on the form but hid it from users. I thought by selecting 'Today' from the drop-down it would automatically pick up the date the form was completed. Instead, it is just picking up the date of the web form's creation.

Is anyone aware of a way to set this up?

Thanks, Jim