Blue Moons and the Rarity of All Black Home Losses

Blue Moons and the Rarity of All Black Home Losses

In recent years the form of the New Zealand rugby team has been spectacular. Some of their recent achievements include:

·         Winning the 2011 World Cup

·         A “perfect season” in 2013

·         Winning all three editions of the Rugby Championship (2012, 2013, 2014), and only losing one of their 18 matches in three editions in the competition.

Of particular interest to me is their form on home turf. Since losing to South Africa in Hamilton in 2009, the All Blacks have won every one of their most recent home games (36). This remarkable feat led me to the following question:

How rare are All Black home losses?

To answer this, I decided to compare All Black home losses with the occurrence of blue moons, which are colloquially known as a rare event. More importantly though, their rarity is measurable or observable, unlike other events such as pigs flying or hell freezing over.

Traditionally, a blue moon was said to occur when there were four full moons in a season (Autumn,  Winter, Spring, Summer), although nowadays the more common definition of a blue moon is the occurrence of a second full moon in a month. For the purposes of this article I will use the latter definition.

Summary of All Black Home Matches by Decade*
	Number of Matches
Time Period	won	lost	drawn	total
1904-1949*	16	7	2	25
1950s	14	5	1	20
1960s	22	2	1	25
1970s	12	6	1	19
1980s	29	4	0	33
1990s	34	7	1	42
2000-2009	50	6	0	56
2010+	35	0	0	35
Total	212	37	6	255

	Percentage of Matches
Time Period	won	lost	drawn
1904-1949	64%	28%	8%
1950s	70%	25%	5%
1960s	88%	8%	4%
1970s	63%	32%	5%
1980s	88%	12%	0%
1990s	81%	17%	2%
2000-2009	89%	11%	0%
2010+	100%	0%	0%
Total	83%	15%	2%

The All Blacks have played at home 255 times since their first home game in 1904 against Great Britain. They have won 212 (83%) of these matches, and lost 37 (15%). The other 6 games ended as draws.

One interesting thing this table shows is that the All Blacks played very few matches in the first half of the 20^th century compared to recent years. The All Blacks have played more home test matches in the past five years (35) than they did in the 47 year period between 1904 and 1949 (25).

The win percentage table shows that their success rate has tended to improve over the years. Up to 1950 the All Blacks had won 64 percent of their home test matches. Between 2000 and 2009 they won 89 percent of their home test matches.

The next table compares the number of home losses with the number of blue moons by decade.

All Black Home Losses vs Blue Moons 1904-Present
Time Period	AB home losses	Blue Moons
1904-1949	7	19
1950s	5	4
1960s	2	5
1970s	6	3
1980s	4	4
1990s	7	5
2000-2009	6	4
2010+	0	1
Total	37	45

This table shows that in the period since the All Blacks played their first match in New Zealand, there have been 45 blue moons and 37 home losses. This essentially proves that you can legitimately answer my earlier question by saying that:

“All Black losses at home are rarer than blue moons”

You could argue that the period from 1904-1949 shouldn’t be included in this analysis, given that the New Zealand rugby team played so few games in the first half of the 20^th century. For this simple study however, I am including the entire period for completeness.

So how does New Zealand’s home record compare with the home record of some of the largest rugby playing nations?

Rugby Test Match Home Losses for Other Nations 1904-Present
Nation	Home  Losses
Australia	110
England	88
France	112
South Africa	52
Wales	119
New Zealand	37
	
Blue moons in same period	45
Summary of Rugby Test Home Matches by Selected Nations 1904-Present
	Number of Matches
Nation	Wins	Losses	Draws	Total Matches
Australia	170	110	11	291
England	193	88	25	306
France	219	112	11	342
South Africa	160	52	11	223
Wales	187	119	11	317
New Zealand	212	37	6	255

The last two tables here show that none of the other rugby playing nations listed here can make the same blue moon claim I made for the New Zealand team. I think it is highly unlikely that any other team would be able to make this claim either, because to achieve it, a team would only be able to lose at home once every 2.5 years (on average).

So in conclusion, my question was:

How rare are All Black losses at home?

And my answer, backed up by statistics is:

“All Black losses at home are rarer than blue moons”

And it is highly unlikely that other rugby playing nations can make the same claim.

Thanks for reading