
There is no possible way in which we could calculate how many flights we've taken nor the number of air miles travelled during our lives. I'm sure it's many many times the average.
Thankfully for us, aviation is a cut-throat industry with players which come and go. Deregulation and competition have kept ticket prices nearly the same as they were in the 80s. In fact, due to rise of Asian economies, the cost of flying over the Pacific Ocean is cheaper than it has ever been.
"The captain has requested you fasten your seatbelts as this turbulence will likely continue."