He's not asking about his build sheet. His Billing history sheet (which is provided with purchase of PHS documents)

I just looked at mine, and can I see exactly what you're talking about. But my columns 74 thru 80 (which I agree are not referenced at all on the zone copy provided by PHS) are blank. I do not have any numbers in these columns at all like yours does.

You have an interesting mystery. Will be interesting to know if someone has an answer. Have you tried contacting PHS directly to see if they can shed some light? I can think of no better source to try...