cost per kg

The threads are long and multi-topical.
I note figures regarding the cost per kg of REE as ranging from $20/kg to $50/kg projected over the next 6 to 12 months.

If one takes into account the interest on loans, due dates for payments to MK and so on over the next 6 to 12 months plus all other outgoings what have folks derived as the total cost per /kg at say a production rate per annum from 5 mtpa up to 11 mtpa and most importantly how did you derive this figure.

Clearly if the outgoing equates to say $30 / kg over the next 6 to 12 months and we get back $25 per kg then we are in strife and therefore I feel this deserves its own thread.