Backing out Energy from the trade balance equation, the US then has a significant trade surplus with Canada.  That may be the largest incentive the USA has for not pressing Canada too hard on NAFTA.

The reason why energy should be backed out of the equation is two fold.

One is that we are not hearing complaints in the United States that Canada is dumping cheap energy.

Two being that the proportionality clause in the energy chapter allows the US to force minimum Canadian energy exports to the United States. One cannot have such a provision and then use the Energy trade imbalance in the formula.

Canada would be far better off distributing some of that US energy East/West/North for domestic use and diversification of export target countries.