When I was filling out my application, I had to fill out a record of all my trips and it gave me a calculation of number of days within the application. There was no separate form that I had to fill out and attach with the application. So my understanding is that the physical presence calculator is 'built in'. I see it in a pdf of my application I downloaded as well. Did you have to do it differently? Unfortunately I cant attach a snip from my application as this forum interface does not allow it. URLs only.