Accuracy of Nearly Extinct Cohort Methods for Estimating Very Elderly Subnational Populations

Table 1

Nearly extinct cohort methods tested at a state level.

	SR variants	DG variants	SRA variants	Proportional variants
No constraining	SR (5, 5, NC)	DG (1, 5, NC)	SRA (5, 5, NC, 10)	Prop SR NC
Constrained to total official estimates for ages 85+	SR (5, 5, 85+)	DG (1, 5, 85+)		Prop SR 85+
Constrained to total official estimates for ages 90+	SR (5, 5, 90+)	DG (1, 5, 90+)		Prop SR 90+

Note. The notation is method (age range, number of cohorts for averaging survivor ratio or death ratio, and official population estimate used as a constraint). In the case of the SRA method, the last parameter refers to the number of older cohorts over which survivor ratio change is measured.