Abstract
The aim of this study is to decompose the number of forestry laborers into period effects, age effects, and cohort effects. Previous researches on the tendency of forestry laborers have studied the cohort changes, either in rates or numbers, and estimated the numbers in the future, using the data of Population Census of Japan. Although the numbers on each period and at each age class are affected not only by their situations at that time and at their ages, but also by the characteristics of their cohorts, there are no analyses on forestry laborers in the past taking account of these three effects specifically. We adopt the Intrinsic Estimator （IE） as a method. We find the age effects were most prominent, making a single peak pattern with the peak of 55-59 age class, the period effects were scarce, decreasing from 1980 to 2005 and raising from 2005 to 2010, and the cohort effects have a peak on 1931-1935 birth-year-cohort and decrease thereafter and raise again from 1971-1975 birth-year-cohort.
