Health in the Time of Leeches

I'm a Weston A. Price follower. It's been great for me and my family, but I've always wondered what the real lifespan and health of people was "back in the day". You always hear how the "average lifespan" was like a miserable 28 or something like that. In my mind, people must have keeled over in their 20's, right? That would make a 40 year old the village elder, correct? This really bothered me, so I wanted to get a better picture.

Luckily, my wife comes from some extremely old American families that have extensive records reaching back into the 1600's, when the original ancestors sailed to America. I dissected (and I mean dissected) one of these record books on the Slocum family, which came here in 1630. The book has records of many of the Slocum descendants up to 1881, when the records were compiled into a book. So, being the ex-engineer and number-lover I am, I went through page by page and recorded the ages of every person who made it into adulthood (I used 16 as the cutoff age) born before 1811 (since the book ended in 1881, I couldn't well ascertain the age of people born 1811 or later).

A few caveats: 1. I discarded mention of anyone who died before 16, as their immune systems may not have been at full "adult strength". I just wanted to see how long you could expect to live IF you became an adult. And while I am not a huge lover of modern medicine, I must admit that there are huge jumps in decreasing child mortality.
2. There were many, many people with incomplete information, so I did not put them in or try to guess an age.
3. If I had a date that I knew they lived to and it was fairly long (past 60), I put them down for that proven age. This wasn't many people, but there were a good many who were born in, say, 1804 and made it to 1881 when the book was published. They may have lived an extra 10 years, but I put them down at the age "proven" by the book.
4. I ignored people who died violent deaths (most didn't list cause, though).
5. The Slocums were fairly well off, and were mostly farmers or mariners, not inner-city dwellers.

Anyway, out of 629 people in the study, here's what I found:

The average age at death was 63.8 years
The median age at death (50% under, 50% over) was 68

As far as people dropping their 20's, here's what I found:

6% died between 16 to 29
6% died in their 30's
9% died in their 40's
12.5% died in their 50's
19.5% died in their 60's
29.5% died in their 70's
13.5% died in their 80's
and a lucky 3.6% died in their 90's
No one made to the century mark, though there were 2 people who made it to 99 (bet they were pissed they didn't get that extra year)

So, even though they slapped leeches onto their bodies, ate herbs and had little sanitation, the majority of people became grandparents or great-grandparents. Basically, the notion that we are SO much healthier and live SO much longer is crap. We don't, and my guess is that nothing has changed for my cohorts. But it's good to know -