I was able to match the number in Line 5/IT-196 by adding these:
*From W2 - NY state tax withholding
*2018 estimated tax prepayment to NJ in 2018
*2017 estimated tax paid to NJ in 2018
*2017 NJ Taxes paid in 2018
You can also use copy of the Federal Schedule A form (2017 Version) > State and Local Taxes to derive this number. You need to switch the years from 2017->2018 and 2016->2017
