x structure is one of the most important characteristics of population composition. Almost all population characteristics vary significantly with age. Age statistics form an important component of population analysis, as most of the analysis is based on age-sex structure of the population. The usefulness of age data is more noticeable when it is cross classified by variables like marital status, literacy educational attainment, economic activity which vary with age in different patterns. Apart from purely demographic concerns, the age- sex data structure is required for age specific analysis of data for planning, scientific, technical and commercial purposes. The dependency ratio, which is the ratio of economically active to economically inactive persons, is dependent on age composition. India has one of the largest PROPORTIONS of population in the younger age groups in the world. 35.3% of the population of the country has been in the age group 0-14 years at the Census 2001. 41% of the population account for less than 18 years of age. Census 2001 data on marital status of persons show that out of over a billion population of the country, 513 million (49.8%) have reported AD ‘Never married’, mainly due to high proportion of young people. The ‘Married’ constitute about 45.6% of the total population.TABLE 6: POPULATION IN DIFFERENT AGE GROUPS AND THEIR PROPORTIONS TO TOTAL POPULATIONAge group Population PercentageAll Ages 1,028,610,328 100.00 - 4 110,447,164 10.75 - 9 128,316,790 12.510 - 14 124,846,858 12.115- 19 100,215,890 9.720 - 24 89,764,132 8.725 - 44 284,008,819 27.645 - 64 139,166,661 13.565 - 79 41,066,824 4.080+ 8,038,718 0.8Less Than 18 422,808,543 41.1Less than 21 492,193,906 47.9Age no stated 2,738,472 0.3Source : C2 and C14 Table, India, Census of India 2001. The number ‘Widowed’ persons, mostly females, are more than 44 million in the country. In the age group 15-49 years, the prime CHILD bearing age group, 81.4% of the women are married. This percentage is high due to lower female age at marriage in many parts of the country. TABLE 7: POPULATION BY MARITAL STATUS AND SEX: INDIA – 2001Marital status Number of Persons ( in '000) Percentage (%)Persons Males Females Males FemalesTotal 1,028,610 532,157 496,454 100 100Never Married 512,668 289,619 223,048 49.8 54.4Married 468,593 231,820 236,773 45.6 43.6Widowed 44,019 9,729 34,290 4.3 1.8Divorced / Separated 3,331