"What are the odds?" The Chances of a Canadian Team Winning the Stanley Cup Are Helped By 2021's Unique Playoff Structure

This season, due to the ongoing pandemic, the 2021 NHL division alignment's were changed, such that the 7 Canada teams only played eachother, including over the first 2 rounds of the Stanley Cup playoffs. Notably, no Canadian team has won the Cup since 1993 - a 26 season drought. 

This year's playoffs guarantee a team from Canada will make the semifinals - which of course increases the chance of that team making the Finals (something that's only happened 5 times since 1993), and subsequently winning it all. So how does this help (or hurt) the chances of a Canadian team finally winning the Cup again?

I'm looking to isolate the impact of the postseason format, so it's not as simple as proportionally taking the number of Canadian teams over the number of teams in the league each year (for example, when the league added 2 American teams in 1993-93, 8 Canada teams / 26 total teams = 31% Cup pre-playoffs). Since Canada teams have not been evenly spread across divisions (such as none in the Metropolitan), I want to start the analysis with the initial playoff field each year.

Just accounting for the number of Canadian playoff teams, the best chances since '93 have been 1996, 2004, 2015, and 2017, when 5 teams made the playoffs. Proportionally that would be a 31% chance - 5 / 16. Using this methodology, there is only a 0.23% chance that no Canadian team has won in the past 26 playoffs.

This divisional discrepancy affects the playoff matchups too - so I also broke down each round by seeding. The team with home ice and the higher seed is expected to win about 64% of the time, and calculating this across the entire playoffs identifies 2017 as the single best chance for a Canadian victor - 34%  that year. Using this methodology, there is only a 0.47% chance of no Canadian team winning it all since 1993.

As mentioned before, the impact this year comes from the guarantee of a team in the semifinals. So I took this a step further and looked at the odds of having no Canadian teams in the semifinals.

This ranges from 2016, when no Canadian teams made the playoffs, to 2017, when there was an 80% chance of having >= 1 Canadian team in the semis. More than one team can make it that far too, but this doesn't outweigh the fact that in no year is there a 100% chance of 1 team. If every semifinalist has a 25% of winning from there, this only shrinks the odds further (full table below). Using this methodology, there is a 2.06% chance of no Canadian team finishing their run as champions in the past 26 seasons.

Season	Count CAD	Odds 0 in Semis	Odds >= 1 in Semis	Odds Win
1994	4	31%	69%	17%
1995	4	31%	69%	17%
1996	5	34%	66%	17%
1997	3	61%	39%	10%
1998	3	61%	39%	10%
1999	3	36%	64%	16%
2000	3	47%	53%	13%
2001	4	40%	60%	15%
2002	4	40%	60%	15%
2003	4	31%	69%	17%
2004	5	26%	74%	19%
2006	4	31%	69%	17%
2007	3	36%	64%	16%
2008	3	47%	53%	13%
2009	3	47%	53%	13%
2010	3	47%	53%	13%
2011	2	55%	45%	11%
2012	2	55%	45%	11%
2013	4	31%	69%	17%
2014	1	85%	15%	4%
2015	5	26%	74%	19%
2016	0	100%	0%	0%
2017	5	20%	80%	20%
2018	2	55%	45%	11%
2019	3	36%	64%	16%
2020	3	61%	39%	10%

Across all three methodologies, there are not many occurrences of Canada having a better than 1 in 4 chance to win it all. Even when considering the outcomes where more than 1 Canada teams reach the semifinals, the downside chance of no Canada team making it that far greatly reduced their odds in any given year. In this context, having at least a 1 in 4 shot at winning the Cup this year represents one of the best opportunities in almost 3 decades.

Season	Count CAD	Proportion Odds	Home/Away Odds	Home/Away, Semis-On Odds
1994	4	25%	25%	17%
1995	4	25%	25%	17%
1996	5	31%	24%	17%
1997	3	19%	11%	10%
1998	3	19%	11%	10%
1999	3	19%	21%	16%
2000	3	19%	16%	13%
2001	4	25%	20%	15%
2002	4	25%	20%	15%
2003	4	25%	25%	17%
2004	5	31%	29%	19%
2006	4	25%	25%	17%
2007	3	19%	21%	16%
2008	3	19%	16%	13%
2009	3	19%	16%	13%
2010	3	19%	16%	13%
2011	2	13%	13%	11%
2012	2	13%	13%	11%
2013	4	25%	25%	17%
2014	1	6%	4%	4%
2015	5	31%	29%	19%
2016	0	0%	0%	0%
2017	5	31%	34%	20%
2018	2	13%	13%	11%
2019	3	19%	21%	16%
2020	3	19%	11%	10%