State tax filing

@ErnieS0 @MaryK4 what about my case below:

 

Over the years, I have contributed to non-deductible IRA for $100,000 (this is all after tax money), now it grew to $200,000.

 

in 2021, I, first time, converted $80,000 to Roth IRA,

so in the NJ previous taxed amount line, shall I put $80,000 or $100,000?

 

In either case, my converted amount ($80k) is less than my basis ($100K), so I should have 0 tax liability, right?

 

This is different from the Federal tax calculation.  In Form 8606, the taxable amt is

 

$80k (IRA distribution/converted to Roth) x  ($100k after tax basis/ $200k current value) = $40K

 

I certainly like the NJ way of calculating, but since it's different from federal calculation, I want to make sure I am doing it correct!

 

Thanks!