From Wikipedia:
Human life expectancy is a statistical measure of the estimate of the average remaining years of life at a given age.
What you described would be the median, not average. Those can be very far apart, a good example is the distribution of wealth. Put 10 homeless people in a room with Bill Gates and everyone's a billionaire on average.
The median is an average. There's generally three types of average, Mean (what you're talking about), Median (the one they're talking about), and Mode (the one rarely talked about).
Sorry for being nitpicky and thanks for naming them all. I just assume the term average is equivalent to mean average in peoples heads. For uneven distributions, like wealth or life expectancy are I assume, mean average in itself just wouldn't be a useful measurement.
Average has a definition of being the mean, median, or mode, BUT it also has a definition that it is a synonym for the mean.
A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The most popular seem to be lighthearted clever little truths, hidden in daily life.
Here are some examples to inspire your own showerthoughts:
If you made it this far, showerthoughts is accepting new mods. This community is generally tame so its not a lot of work, but having a few more mods would help reports get addressed a little sooner.
Whats it like to be a mod? Reports just show up as messages in your Lemmy inbox, and if a different mod has already addressed the report, the message goes away and you never worry about it.