I just did the math, and from December 7, 2007 to today, October 24, 2008, I've lost around 24% in my retirement funds.
Remember, if your accounts decrease by 10%, you need to make more than 10% to break even. Thus, my portfolio has to go up 32% so I can get back to where I was in December 2007. Sigh.
Update on October 27, 2008: another blogger is in the same boat: