As I said at committee a couple of weeks ago, the accomplishments to date are partly the result of regulations we have created for the transportation sector and the coal-fired electricity generating sector. This will be further contributed to by the oil and gas regulations, which we're working to complete, and those for other major emitters.
They are also the product of actions taken by provinces, by municipalities, and by ordinary Canadians through practices such as keeping the thermostat a couple of degrees cooler in the winter and perhaps using the air conditioning more judiciously in the summer, things that would seem to have a relatively minor potential impact. There's some confusion, which is completely understandable, between the numbers and the megatonnage we report in our annual inventory updates, and the estimate of what our regulations to date and supplementary contributions will make by 2020.
I've been waiting for an opportunity to explain this, so thank you for your question. If we had done nothing, as, for example, the previous Liberal government did, we would have had an estimated business-as-usual megatonnage of about 850 megatonnes, plus or minus five or ten megatonnes, by 2020. The actions that have been taken to date—supplementary actions by the provinces and industry—have brought us down to an estimated 720 megatonnes by 2020. That has nothing to do with the latest inventory report that says 702 megatonnes.
The 2005 megatonnage was 737 megatonnes. Reducing that by 17% would take it down to 611 megatonnes. So from 850, and we're at 720, we're just over halfway to getting down to our 2020 total target emission reduction of 611 megatonnes.