Vintage

Version. What flavor was it? What was the nose, the finish?

Yes, mortgage traders treat series of mortgage backed securities like they are fine wines...or cardboard box screwtop ones. Mortgages are issued over long periods of time, and most last 30-ish years, to boot.

In different eras, mortgages carried different levels of scrutiny, restriction, tension. So in the 2011-ish era, post-mortgage crisis, you can bet that anyone who received a mortgage was extremely well vetted as having good credit, the ability to pay, real backing, etc. In the 2004-2006 era, kinda the opposite.

So when you're assaying a group of 1,800 mortgage units with, give or take, $300,000 remaining in principal, the vintage matters. It sorta reflects the era in a very strange, semi-American-Dreamy kind of way.