Learn the difference between arithmetic average and median. People use sloppy terminology all the time, saying "average" when they are actually talking about "median".
Averaging is meaningless, as you pointed out.
The median age is what is used in talking about mortality statistics.
This: Actuarial Life Table is what should be looked at when we are discussing mortality & longevity.
Look at the rows for age 66 and age 82. For every 78,351 males that are 66, only 41,683 will still be alive at 82. IOW, 53% will make it to 82 and 47% won't. That's about 50/50. On the age 66 row, we see the Life Epectancy of a 62 year old male is a little over 16 years. 66 + 16 = 82.
Life expectancy at age X is defined as the number of years it takes for the number of people who are still alive to be half the original number.
So... a 62 YO male has a 50/50 chance to make it to 81.
A 70 YO has a 50/50 chance to make it to 84.
An 80 YO has a 50/50 chance to make it to 88.
Now, we are worried that me might be one of the unlucky (?) 53% and live past 82 and don't want to risk running out of money.
So we could define an "optimistic life expectancy" as 25% chance of still being alive.
Age 62 = 83,217 50% of that is 41608. Closest row to that is 82 with 41,683 survivors. This is the normal 50/50 L.E.
Age 62 = 83,217 25% of that is 20804. Closest row to that is 88 with 21,785 survivors. This is the optimistic 25/75 L.E.
Marine Corps method. "Look at the man on your left, look at the man on your right. When it's all done, only one you will still be here."
Age 62 = 83,217 33% of that is 27739. Closest row to that is 86 with 28,341 survivors. This is the "marine" 33/67 L.E.
Let's go crazy. What's the stats for 62 year olds making it to 90?
Age 62 = 83,217 Age 90 = 15,722. That's 19%.
For your poker table club of 5 guys of 62 years old, only 1 will make it to 90. The other 4 will be gone.
Averaging is meaningless, as you pointed out.
The median age is what is used in talking about mortality statistics.
This: Actuarial Life Table is what should be looked at when we are discussing mortality & longevity.
Look at the rows for age 66 and age 82. For every 78,351 males that are 66, only 41,683 will still be alive at 82. IOW, 53% will make it to 82 and 47% won't. That's about 50/50. On the age 66 row, we see the Life Epectancy of a 62 year old male is a little over 16 years. 66 + 16 = 82.
Life expectancy at age X is defined as the number of years it takes for the number of people who are still alive to be half the original number.
So... a 62 YO male has a 50/50 chance to make it to 81.
A 70 YO has a 50/50 chance to make it to 84.
An 80 YO has a 50/50 chance to make it to 88.
Now, we are worried that me might be one of the unlucky (?) 53% and live past 82 and don't want to risk running out of money.
So we could define an "optimistic life expectancy" as 25% chance of still being alive.
Age 62 = 83,217 50% of that is 41608. Closest row to that is 82 with 41,683 survivors. This is the normal 50/50 L.E.
Age 62 = 83,217 25% of that is 20804. Closest row to that is 88 with 21,785 survivors. This is the optimistic 25/75 L.E.
Marine Corps method. "Look at the man on your left, look at the man on your right. When it's all done, only one you will still be here."
Age 62 = 83,217 33% of that is 27739. Closest row to that is 86 with 28,341 survivors. This is the "marine" 33/67 L.E.
Let's go crazy. What's the stats for 62 year olds making it to 90?
Age 62 = 83,217 Age 90 = 15,722. That's 19%.
For your poker table club of 5 guys of 62 years old, only 1 will make it to 90. The other 4 will be gone.
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