perceptions_now wrote on Nov 26
th, 2015 at 2:40pm:
So Maqqa, I hope you have now, at least, actually read a little of your own reference and you now have "some" understanding, at least of "some" of the Demographic issues now in play?
Growth rate is interesting and the fact that you think population will decrease to 3-4 Billion. Half the world will die off? How would you reconcile this with life expectancy data saying we live longer and medical advances keeps us all living longer
In my link look at how long it took to reach each billion of population.
Even by your reduced rate of increase - the increase is applied to a larger base. For example
2% increase on 4B gives a different number than 2% on 7B
So read the link again and see that
(1) It took the world 1800 years to reach 1B people
(2) It took the world 200 years to go from 1B to 7B
(3) 3B to 4B it took 14 years
(4) 4B to 5B it took 13 years
You assume the fertility rate have a direct correlation to total population. This is why you've posted a decline in total population
A simple analysis shows a direct application is useless.
Lets assume when the world was at 2B and assume 50/50 male/female. This means there's 1B females And assume all female is able to bear children. If each female bear 3 children means the population increase by 3B
When the world is at 7B - the same assumption means 3.5B females. If each female has 1 child this still mean 3.5B increase
So despite a drop in of fertility rate from 3 to 1 - the population is still growing
You still have not taken into account China just removed its one child policy
Have you taken into account the Infant Mortality rate over the period you've stated i.e. 1950 to 2015
In the example you posted - Fertility rate in 1950 is 4.95
Infant Mortality rate for China went from 122 to 22
Infant Mortality rate for India went from 165 to 63
This means females breed more but more died
Over to you
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