Retirement tax questions

Macuser_22,

Thanks for all your advice and support of the community.

What are your thoughts about a situation where no 8606 have been filed for ten years.  No deductions have been made.  No distributions have been made.   IRA Traditional and Roth IRA exist.   Prepared to file all back 8606 for each year.   The question is where to start and how to calculate basis in 2019?   If the prior year 8606 forms were not completed, what basis to use on line 2 of the 2019 form?

Thanks!