For those interested , and to help with any conversion...

For those interested , and to help with any conversion calculations the "m" is the old Roman number for 1000, so mm is 000 000 or 1,000,000 which is a million. The other thing to remember is it is a volume, hence the word cubic feet in the flow rate language
so a flow rate of 20 000 000 (20mm c.f. ) @ $605 per (m) is 1000 *.65/100 = $78, 650 per day, minus costs etc
so Spiders figures of $ 18 million per year per are correct minus costs royalties tax anf other down time issues. However somthing to bear in mind, doe cannon av pressure for these flow rates is 2800psi (ours is 2300)