purchased coop during the year, in 1098 box 2 should I enter my share of the coop's mortgage debt as of my purchase date?

I purchased a coop in April 2019, received 1098 from my coop which told me the corporation's outstanding mortgage principal on a per share basis as of Jan 01, 2019.  My question is what should I enter in box 2 on TT:
- my share of the coop's outstanding mortgage as of Jan 01 2019
or
- my share of the coop's outstanding mortgage as of April 2019 when I bought the place? 

if the latter, I don't actually know the outstanding balance for the coop's mortgage as of April. What should I put in box 2 in that case? 

Thanks in advance.