With regard to the specific application of the factors, Madame Thivierge just listed them clearly. There has been, in the context of negotiating NAFTA--that's more than 15 years ago--a general lifting of and an increase in the review threshold as a measure that was put for NAFTA investors and then subsequently applied to WTO investors.
But pertaining to your question, I think Madame Thivierge answered in terms of what the factors are.