National Bank mentioned a few of the driving factors for stock price increase this year. It looks like analyst are starting to catch on to what has already been mentioned here.
https://www.theglobeandmail.com/investing/markets/inside-the-market/article-fridays-analyst-upgrades-and-downgrades-for-jan-26/
You should be heavily levered, if you are 30 years from retirement and your entire portfolio is less than one half years income.
You probably should not be heavily levered, if you are less than 20 years from retirement and your entire portfolio is multiples of your annual income.