[sumo] Yokozuna/ozeki life span

[Magnus Berg]

Forgive me if I try to drag the discussion away from Asashoryu for a 
second... After the (too early) death of ex-Kotozakura, I compiled some 
statistics of the life-span of yokozuna. I added the ozeki of the 
period, to make the "survey" a bit more relevant. I am aware that this 
says close to nothing statistically, but it may be interesting 
nonetheless.

I divided the ozeki and yokozuna into decades after year of death, to 
see if some progress could be seen.

1960's
Yokozuna:
Tsunenohana, died in 1960, 64 years old.
Futabayama, 1968, 56.
Musashiyama, 1969, 59.
Haguroyama, 1969, 54.
Ozeki:
Asashio II, 1961, 82.
Shimizugawa, 1967, 67.
Wakahaguro, 1969, 34.

Average age of death: 59

The 1970's was a dark decade for yokozuna, with no less than 6 dying 
before the age of 60, three of them in 1977.
Yokozuna:
Tamanoumi, 1971, 27.
Minanogawa, 1971, 68.
Maedayama, 1971, 57.
Azumafuji, 1973, 51.
Terukuni, 1977, 58.
Chiyonoyama, 1977, 51.
Yoshibayama, 1977, 57.
Akinoumi, 1979, 64.
Ozeki:
Nayoroiwa, 1971, 56.
Itsutsushima, 1973, 61.
Noshirogata, 1973, 78.
Saganohana, 1975, 57.
Tochihikari, 1977, 43.

Average age of death: 56

The 80's saw the death numbers decrease significantly, but quite a few 
ex-ozeki died at a not-too-high age.
Yokozuna:
Asashio, 1988, 59.
Ozeki:
Kotogahama, 1981, 53.
Shionoumi, 1983, 65.
Masuiyama I, 1985, 66.
Ouchiyama, 1985, 59.
Matsunobori, 1986, 61.
Mitsuneyama, 1989, 67.

Average age of death: 61

The 90's - what happened? Only these two yokozuna, no ozeki!
Tochinishiki, 1990, 65.
Kashiwado, 1996, 58.

Average age of death: 61,5

So far in the 00's, we have these:
Yokozuna:
Kagamisato, 2004, 80.
Kotozakura, 2007, 66.
Ozeki:
Takanohana, 2006, 50.
Hokutenyu, 2006, 45.

Average age of death: 60

So from the 60's until today, not much has changed, with the average 
age still around 60. This of course only applies to the two top ranks, 
the picture might be different if we were to look at all rikishi. Still 
seems to me that far too many die before reaching that age (19 since 
1960, compared to only two in the list above who have reached 70).

The oldest living yokozuna is Wakanohana I at 79. Sadanoyama and 
Tochinoumi are both 69, Taiho 67. Oldest ex-ozeki is Kitabayama at 72 
and Yutakayama who celebrated 70 two days ago.

I'm sure I have made some mistakes or left someone out, please point 
out in that case.

/Maguroyama