In fact, the most significant aspect on refining margins is actually the crude price differential, in that eastern Canadian refineries are still largely dependent on imported Brent benchmarked crude where western refineries have 100% access to a lower-priced WTI benchmark crude. That would be the most significant aspect of that refinery margin difference between east and west.
There are other competitive dynamics in terms of the market. The interior part of Canada in the west is a largely landlocked market. It has less access from foreign sources of supply. Eastern refineries compete in the Atlantic basin market for which there are many more alternatives to supply because much of that market is adjacent to tidewater and fuel now is a product that is traded internationally, no longer just on a North American basis. There are a number of factors but certainly crude price market differences would be the bulk.