Facebook Inc. began trading publicly on Friday following one of the most anticipated stock offerings in history. The initial public offering of stock priced at $38 on Thursday. It was at the top end of a projected range that Facebook had already increased just days earlier.

Although many investors had hoped for a big first-day pop, Facebook's stock opened Friday at $42.05 and fluctuated between $45 and $38 throughout the day. It closed barely above its IPO price, at $38.23.

Here's how Facebook's stock has traded since the IPO:

_ Friday: Closed at $38.23, up 0.6 percent from IPO price.

_ Monday: Closed at $34.03, down 11 percent for the day, down 10 percent from IPO price

_ Tuesday: Closed at $31, down 9 percent for the day, down 19 percent for the week, down 18 percent from IPO price