One way to understand the future of a society is to look at the age of its population.When the number of people gets bigger over time,this is population growth.if we add up the ages of all people in a country and divide it by the total number of people,we get the average age of the population.in many countries,this average age is increasing.the biggest growth is taking place in the category known as "seniors ",people over 60 or 65.many of them have worked hard for most