18-20 sts5 hours. I worked on that Excel spreadsheet for 5 hours. I did save it at 7:36pm but continued to work on it. Apparently, I have it set to NOT save when I shut it down. What a pain in my ass. Pardon me, while I go yell at the computer.
EDIT: It's now 11:29 pm (Or 12:29 am if you have already changed your clocks!) and I recreated the entire spreadsheet. And yes, I saved it. :)