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Updated: Sep 29, 2026

Measurement of Lifespan in Drosophila melanogaster
Published on: January 7, 2013
[The use of the age concept in monthly population figures]
Abstract:
"In Dutch population statistics age is usually defined as the year in which a demographic event occurs minus the year of birth. This age concept is referred to as age on 31 December. As a consequence of determining age in this manner, interpreting age-specific monthly figures is sometimes difficult.... Statistics Netherlands prefers the concept of age on 31 December for two reasons: it facilitates the linking of cohort and period data in the case of annual figures; using one concept for annual and monthly figures avoids consistency problems." (SUMMARY IN ENG)
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