Canadian North has posted the 2017 Lowest Return Airfares for tax purposes. Follow this link to see them: 2017 VTA Rates.pdf
If you have a Box 32 amount on your T4, you are able to claim your trips out of the north - up to 2 trips per household member per year. To claim you must calculate the lowest of: 1-your Vacation Travel Assistance (VTA) benefit (Box 32), 2-your actual travel expenses, and 3-the Lowest Return airfare to your closest southern point.
That's where this list from Canadian North comes in handy!