Absence calculation

Just want to double check the absence calculation for naturalisation (spouse of British citizen - 3 years).

I have to list absences from the UK during the last 3 years. So if my application is on 18 October 2020, do I list all absences from 17 October 2017, or do I need to list all absences for the full 2017 period (e.g. 1 January 2017 - 18 October 2020). I suspect the former, but want to check.

Do I need any other evidence to show I was present in the UK 3 years before the date of application, or is my passport with all the stamps sufficient?

Thank you

I suggest you list absences from 19 October 2017 as you should have been physically in the UK on the 18th.
Absence listing is all that is required - you don't need to prove every date. Your passport with stamps in/out is required anyway.

Thanks, very helpful!