There have been many studies about how, thanks to improved medicine and healthcare, our world population is ageing. The highest impact of this is on pensions and the burden on the governmental financial systems currently in place, which, as the baby boomers begin to reach retirement age, will soon be unable to support the necessary numbers.
Below are two graphics which illustrate this very effectively, beginning from the 1960s and going all the way up to 2060, to demonstrate in real terms how quickly this is happening. The situation in Europe is worse than that of the Americas; but on all three continents, at the current rate, the median age of the population will be over 40 almost everywhere by 2060.