Time to complete multi page form

What is the best way to see how long people take to fill out my form when it has multiple pages? 

The timer widget seems to only time how long it takes on one page.

I tired putting a timer on every page and using a formula column to sum them, but that did not work. I think the issue is that the timer widget creates a text column rather than numbers. Of I am setting up the function column wrong. 

There are two widgets, which can track how much time it takes to fill your forms. You can find them below:

https://widgets.jotform.com/widget/time_tracker

https://widgets.jotform.com/widget/fancy_timer

The Time Tracker widget is easy to add to your form. It does not have additional settings, because it does not appear on your form. The timing is anonymous. The total time tracked will be recorded and saved along with the responses.

The Fancy Timer widget displays a time counter, which tracks how long your users will use to complete the form.The widget comes also with beautiful themes, which you can customize.

Let us know if you need any further assistance.