PS4 space related problem

I bought a 500GB PS4 back in January early this year from Amazon.

Now, 500GB will mean 465GB because it's never the "actual size" advertised - like how 1TB is actually 932GB.

And if I remember correctly, I had 403GB of free space free when I first used it, so that's about 62GB for the OS. (Guessing~)

As you can see from this screenshot [imgur.com], I'm only using 96.13GB total of space.

So 96.13GB of used space, plus a guessed 62GB for the OS means a total of 158.13GB.

Yet the image tells me otherwise... So, what's going on here?