Deductions & credits

I just don't understand your answer. I beg of you, can you please just tell me

 

When, as I complete the worksheet to calculate my 2020 EITC, if I elect to use the higher 2019 earned income (not AGI but earned income) and in tax year 2019 that 'earned income" I had was as part of a marriage when we filed a joint return, and here I am now divorced and for tax year 2020 as head of household with 2 dependents,   WHICH of the following figures is the "2019 earned income" I am electing to use in those calculations and to put on line 27 beside the notation PYEI?

 

1. Is it 1/2 the total earned income of my ex spouse and myself earned in 2019? (my portion as an individual tax filer in 2020 being 1/2 of what we jointly filed in 2019)

 

or

 

2. Is it the full joint 2019 earned income total of what we both earned while married in 2019?

 

or

 

3. Is it only the exact portion of that 2019 married income that I myself earned (on my own W2, not in any way including any of spouse's earnings) ?

 

(in every case the 2019 figure is higher than my 2020 earned income, but depending upon which I am supposed to use that figure decides my EITC for 2020 tax year)

 

I am needing to amend an already filed turbotax return because I didn't know I cold use 2019 earned income.