Hard drive size calculation error

[x-StoneSour-x]

I've just formatted my computer, re-installed all the software I had before. What gets me though, is that when I check to see the Properties of C:, the size shows up bigger than what all the files are really taking up. If it'll help, the hard drive is also compressed, along with all subfolders/files. Is there a way to recalculate the size? btw I'm 16, I'm new to this site and have little knowledge of computers. Help would be appreciated

 

[PC eye]

The properties screen on the left only reports files that are "read only". That is not the actual total of all files on the drive itself. The 11.gb is far from the actual that would include hidden system files as well as other files with different file attributes applied. The partition of the drive also leaves some other hidden restoration files as well as the master boot record and partition information. You will note the capacity seen at 93.1gb while the amount of "bytes" shows over 100gb. The 93.1gb figure is what is available after partitioning, formatting, and Windows/software installations are complete.