Hi Mark,
I don't know NAT too well - but that is one ugly chart. The company seems cheap based on traditional valuation metrics but here is the catch - it has always been cheap. Oil tanker stocks don't command high valuations and despite its multi-year downtrend, it is actually now trading above historical averages on a P/B and P/S level. Most are trading at single-digit PE ratios and below book value.
There are signs that the industry is primed for a rebound, but it just remains a very un-loved area. That being said, I don't see too much downside from here and it could rebound should the industry finally catch some positive momentum. It hasn't really had much momentum for more than five years now. I should also note that NAT has one of the older fleets, which likely makes it less attractive than some of its peers.
Mat