Yes PAR watts. And from what I am finding most of the HPS bulbs do emit the highest PAR watts even though their graphs suggest otherwise. I don't think the theories are wrong, just that they are not well represented by those color spectrum graphs. I have experience producing graphs of this type so I know how missleading they can be.
See, because a HPS makes a huge yellow spike, the whole graph is pushed way down. That is why I would like access to such a graph. I would omit the yellow spike which would bring the rest of the graph up so we could see the rest of the spectrum.
From my Googling, it appears this might be the best HPS on the market. And it is made by an impressive company.
http://www.ushio.com/files/specs/hiluxgro.pdf
The Hotilux, Sunmaster and Sylvania also claim high PAR wattages. I ran across a list somewhere but can't find it now.