The proportion of isotopes that we produce and comes back to Canada, as you know, after processing, is about 10%. So 90% of it is really for the export market.
I think AECL would be better placed than me to give you a sense of the details of the numbers relating to revenue, which amounts to roughly $35 million to $40 million a year from the sale of isotopes historically—and not just TC-99, but also others—and then the costs of operating the Chalk River facilities and the NRU reactor; therefore, the cost of production of the isotopes. There's complexity in terms of allocation of the costs to the isotopes versus other functions performed at Chalk River and the NRU reactor.