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Two sets of
standard model life table families (Coale-Demeny 1966 and
1989, and United Nations, 1982) are commonly used to derive
a variety of mortality indicators and as underlying
mortality patterns for estimation and projection by the
United Nations and the demographic research community at
large. But these two sets of model life tables - designed
primarily to be used in developing countries or for
historical populations – cover mortality patterns only for a life
span from age 20 to 75. A first extension of these
model life tables was produced by Thomas Buettner in 1998
which extended the initials sets of model life tables from
e(0)=75.0 up to 92.5 using both a limit life table as
asymptotic pattern and the classic Lee-Carter approach to
derive intermediate age patterns (Buettner, 2002). |
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With the
extension of the projection horizon for all countries up to
2100 as part of the 2012 revision of the UN World Population
Prospects, it was necessary to allow life expectancy at
birth to go beyond 92.5 years. In addition, in-depth analysis of the initial 1998 extension revealed
substantial deviation for out-of-sample predictions compared
to the Human Mortality Database experience at very low
mortality levels (especially for Coale-Demeny models, see
Figure 1 in Willmoth et al., 2009), and the need to improve
a smoother transition between the existing set of model life
tables up to age 75 and their extension. A new set extended
model life tables was computed in Spring 2010 by staff of
the Population Division (Gerland and Li) based on the
modified Lee-Carter approach. After extensive
cross-validation against the Human Mortality Database (HMD)
performed by Kirill Andreev some constraints have been
imposed to ensure some convergence toward the HMD mortality
experience at high levels of e(0). The nine families of
model life tables extended up to e(0)=100 were smoothly
blended to the existing ones to insure smooth mortality
surfaces by age and sex and e(0) levels. The new model life
tables can be downloaded below. |
