Matt Mahoney is one of the organizers of the Prize for Compressing Human Knowledge (Hutter prize), with Jim Bowery and Marcus Hutter. The prize is awarded to progress in compressing 1GB of Wikipedia text, so let us try to work out an example from it.
We read in the Wikipedia that Marcus Hutter was born "April 14, 1967". From our prior knowledge of the world (or reading the Wikipedia!), we know there are $12$ months per year, up to $31$ days per month and we are in $2022$ now, luckily close to $2048$. Therefore, we can safely use $4$ bits for the month ($2^4>12$), $5$ for the day ($2^5>31$) and $11$ for the year ($2^{11}>2022$), totalling $20$ bits for a lossless compression of a birth date (CE).
The original string "April 14, 1967" is $14$ characters long, so $112$ bits assuming $8$ bits/character.
Thus some understanding of this tiny bit of information gets a $\frac{112}{20}$ compression factor, about $5.6$. Maybe the comparison makes little sense here, but $5.6$ is similar to the initial $5.46$ compression factor by Matt Mahoney. Of course there are a lot of much more complex information structures in the Wikipedia. Besides, the month length can go up and down some characters, so this sample value is far from a constant for all dates.
Anyway, hopefully this simple example shows some relationship between text compression and understanding.