The formula followed: 



Ar =z 1/c Aa + 1/c Ab + (— a+b) Ac 



c- 

 1/c Aa represents the amount of change in Ar attributable to change by natural causes 



in the age group 0-14. 

 1/c Ab represents the amount of change in Ar attributable to change by natural causes 



in the age group 65 and over. 



— a+b Ac represents the amount of change in Ar attributable to change by natural 



c^ causes in the age group 20-64. 

 AR = 1/C AA + 1/c AB + (- A+B ) AC 



C2 



1/C AA represents the amount of change in AR attributable to change by migration 



in the age group 0-14. 

 1/C AB i-epresents the amount of change in AR attributable to change by migration 



in the age group 65 and over. 



— A+B AC represents the amount of change in AR attributable to change by mi- 



C^ gration in the age group 20-64. 



DEPENDENCY RATIO 



20 



