Image mode S6200

I just got my S6200 and was messing with the settings and it has a image mode. One thing I noticed was the higher on the list the less pictures it says I have on it. What is the difference in the image settings? It has 2 16m settings, then it has 12m, 8m, 5m, 3m, PC, VGA and finally a 16:9 12M setting.

16m = 16 megapixels
The higher the number to better quality you will get.
The higher the quality the less pictures you will get on a storage card.

Shoot the higher numbers and get a larger card or carry an extra one.

Ok, that's what I figured but wasnt for sure.