I always have to look these up.  If a taxpayer doesn't receive a 2019 Schedule K-1 until 2024, what does he do with the NOL it generates?  What were the rules in 2019?  Doesn't it have to be carried back first, for three or two or maybe five years or some other number?  It doesn't depend on the starting date of the company with the loss, it depends on the shareowner's history, right? And there's some rule about an election to carry it forward instead, but doesn't that have to be made on an original return?