in this year's annual letter Melinda and
I take the toughest questions we get
asked and give our answers one that's
come up for a long time is as we make
the world healthier it's the population
we're going to get so big that feeding
everybody and maintaining the
environment is going to be impossible
here we can see a chart that looks at
the total world population over the last
several hundred years and at first
glance this is a bit scary we go from
less than a billion in 1800 and then
three four five six and seven point four
billion where we are today is happening
even faster so Melinda and I wondered
whether providing new medicines and
keeping children alive would that create
more of a population problem what we
found out is that as health improves
families choose to have less children
and this effect is very very dramatic we
find that in every country of the world
this is repeated the population growth
goes down as we improve health so we've
taken that chart that shows the global
population growth and we've actually
extended it out all the way to 2100 and
we concede that instead of continuing it
actually flattens out another way to see
that is through this rate of population
growth and you can see that in the 60s
that reached a pretty high number over
two percent per year and it's now come
way way down now eleven billion people
still a lot but the good news is that
the faster we improve health
the faster family size goes down and so
we can feel great about saving those
lives
you