Whereas, I agree that our reproduction rate is a concern, it's worth noting the infant mortality rate has declined significantly since the late 18th century, as has the mortality rate of children. Comparing rates from the late 18th century to present day needs to take that into account to be meaningful.
Agreed but demographics don't lie. Ethnic Russian men have the lowest average life expectancy in a country where the Muslims population is increasing at an alarming rate. 50 years from now, what will the country known as Russia be like?
Ethnic Spaniards in Spain, where Leftist thinking(or lack there of) has taken hold and the birth rate is the lowest in Western Europe, will disappear in three generations.
We're living longer than ever before simply because a lot of the things that used to kill us in our teens, our twenties, our thirties, etc. either don't affect us anymore or are treated easily through modern medicine.
I heard some futurist on the radio a few years ago, and he said that one of the defining characteristics of this modern age is that something like 99% of the population will die as a result of whatever they were genetically predisposed to die of.