Used space after reformatting

After reformatting my new 2TB My Passport, I noticed that there is about 147 MB of used space. But there’s nothing on the drive since I just did a reformat. What’s up with that? 

What is the total drive size shown? A 2T drive formatted for Windows will show about 1835-1860. It’s a math thing. My 1T internal shows as 931 and drives with Smartware will have slightly less.

Joe

Capacity is 1.81 TB. And I realize that the capicity will never actually equal 2 TB. I just found it puzzling that after reformatting/wiping out everything on the drive, it would list 147 MB of used space when thre was nothing on the drive :S