Assuming [Date New] is coming in as a date field, then it's straightforward.
IF [PWV] = 1.43 and [Factor] = 16.4 and year([date new]) = 2017 then 235896 END
Just be careful about PWV. The value Tableau sees might be .0134, not 1.43. You can tell by displaying it on a sheet.
So you'll get a value on each row. Either 235896 or null.