I unintentionally neglected to include one income payer on my 2016 return. In August 2018, I received notification from the IRS of my error, and told me that had underpaid my taxes in 2016, and that I owed over $4,000.00 in back taxes for 2016, plus $360.00 interest. I paid the back taxes and interest in 2018. How do I handle this transaction on my 2018 return?
