70 years

On average, we spent 5 years in childhood.
On average, we spent 17 years in education. 
On average, we spent 34 years in work. 
On average, we spent 15 years in retirement. 

We spent our childhood pursuing bugs and bees.
We spent our youth understanding the world.
We spent our adulthood climbing the ladder.
We spent our final years pursuing happiness. 

The math does not add up.