[ejstronge]

  We only really live about 6 and a half years longer than we 
  would prior to the industrial revolution on average. This 
  relatively modest number is obscured somewhat by overall  
  life expectancy averages which are buoyed by drastically  
  reduced infant mortality.

I haven't heard this before - where are you getting your data?

[mahyarm]

Life expectancy numbers should be quoted at 'life expectancy at 10 years old' if you want to filter out child mortality in the past.