Population

Due to expensive cost of living, many urban families now opt for ‘We Two, Ours One’ policy of having a single kid. Some countries are also popularizing having one child in a family to reduce population explosion by way of giving tax exemptions. If the trend continues, the terms ‘sibling’,‘brother’ and ‘sister’ are in danger of becoming extinct.

To understand how the ‘Single-child’ policy assists in controlling the population explosion, let us take an example:

Say, in 1975, two couples got married. Lets call them Family A and Family B. So we have 4 people in 1975.
Say, in 1980, these two couples bore one child each. Family A bore a boy and Family B bore a girl. So, we have 6 people in 1980.
Say, in 2005, the boy and girl met and married one another. So, Families A and B now got combined and now consist of 6 people.
Say, in 2008, the boy and girl bore a child. Hence, in 2008, Families A and B now are 7 people in total.
Say, in 2010, the boy and the girl’s parents died. So, Families A and B now are 3 people in total.

So, what do we get? In 1975, the total strength of Families A and B combined was 4 and 25 years later, the total strength of Families A and B combined is 3. That’s a reduction of 1 in the population in a span of 25 years from 2 families.

Lets extrapolate this to actual figures. Population of the world in 1960 was 3031720298 and 3071626008 in 1961. So 39905710 took birth between 1960 and 1961.

The male-female ratio tips in favour of both parties across decades. Also, one man does not bear children with only woman and one woman does not bear children with only one man. So, for the sake of a simple argument, lets ignore all that and consider that out of 39905710, half were men and half were women and the former half married the latter half in 1975 and they all lost their parents due to some natural calamity and hence, the total population of the world then would have been 39905710.

Now lets suppose each couple bore one child in the year 1980. So we have 39905710 + 19952855 = 59858565 as the total population off the world in 1980 and 19952855 (which is 39905710/2) new people added in 1980 alone. To continue the argument in the same vein, we need the number to be even, so lets suppose one child died immediately after birth. Hence, the new population added in 1980 now is 19952854 and half of them are boys and half of them are girls who get married to one another in 2005 and bear one child each in 2008. So, the new population added in 2008 is (19952854/2) = 9976427 and the total population in 2008 is 59858565 + 9976427 = 69834992.

In 2010, the folks who were present in 1975 all died and hence the world’s population in 2010 would now be = 69834992 – 39905710 = 29929282. This is a reduction of (39905710 – 29929282) = 9976428 people in the world in a span of 25 years. That’s almost a 10 million people less!

In reality, between 1975 and 2010, the population grew by over 2.5 Billion people!

:-)