lease buy out that later trade in
2013 leased a car. 2016 bought out the lease. 2021 traded the car for another car. Cars used partially for self-employment business. 2017 was less than 50%. I've used only the standard mileage deduction. How to I account for the trade in on the 2021 tax return. (Perhaps I should have done something different in 2016? I did not report the buyout.)