The world's youngest guy-who-still-has-his-job-at-that-bank

Marshall ran the numbers once more. Which is just a fancy way of saying 'Marshall closed the file valuation.xls and opened it again'. His boss barged in for the fourth time that morning.
'Done? What's the number we are looking at?'
'Er...25'
'Whoa! Sure you don't want to crunch the numbers again, buddy?'
The truth was there weren't too many numbers to crunch. Facebrook had earned a revenue of one dollar for the financial year 2004-5, which was under the column 'won by founder in a beer contest'. Assuming similar incomes over the next few years and a completely arbitrary terminal value of the firm, meant that for the first time since Marshall joined the bank, the cell next to 'enterprise value' had a number instead of an error message. And that number was 25 USD.
'Not really, do you want to check? Here's a print...'
'No, I'm late for the meeting already. Ok, I'll start at 20 then. Hmm. You meant 25 billion right? I'm very sure we can't be talking in millions anymore?'
This stumped Marshall. His world was falling apart in slow motion. And he had to say something in the next 5 seconds. He didn't really have a choice. Going along with 25 billion USD gave him time till this evening to re-work the excel file. Arguing for 25 USD would land him in unemployment for sure, and perhaps at a mental asylum. What had he missed in his model?
'Yeah of course, 25 billion. So, boss, did the founders speak about any other revenues, you know, like money coming in or something?'
'No, that was the best part. We have a winner and...ok gotta run now'.
There was a lot of work to do. Marshall decided to first take a 10 minute break and check his own facebrook profile. For the first time since he'd joined the firm, he didn't feel guilty about facebrooking in office.