In calculating Dependency Ratio, the numerator is expressed as -
Dependency ratio 

The proportion of persons above 65 years of age and children below 15 years of age are considered to be dependent on the economically productive age group (15-64 years).
The ratio of combined age group 0-14 years plus 65 years and above to the 15-65 years age group is known as total dependency ratio.

Total dependency ratio = Age group 0-14 yrs & age group above 65 yrs / Age group between 15-65 yrs

It is also referred to as the societal dependency ratio and reflects the need for a society to provide for their younger and older population groups.
Population under 10 years and 60 and above
Population under 15 years and 60 and above
Population under 10 years and 65 and above
Population under 15 years and 65 and above