Food for thought: Citigroup right now is trading at a value that puts its market capitalization at just south of $22 billion.

That means it trades at a discount to the $25 billion purchase price of the preferred stock purchased by taxpayers, through Treasury and TARP.

If you sold all the common of Citi, you could not raise the cash to pay back the taxpayers.

Doesn't seem like such a great investment, does it?

Courtesy of the folks at Dow Jones Indexes, here are some stats after today's sharp drop:

- The current month is actually worse than October, which was pretty darned bad.

- If the DJIA were to end at this level now, it would mark the end of the worst two-month period since April and May of 1932 (30.4 percent now vs. 38.95 percent then).

- This is the biggest two-day drop since the two days ended Oct. 20, 1987, or the last big crash.

- The DJIA is now 47 percent from its record close, which makes it a worse bear market than the 45 percent drop in 1973-74 and the worst since the 1937-1938 bear market.

- If the Dow falls further so that it drops 49 percent, it will be the worst since the 1929-1932 Great Depression bear market (though the Dow fell a whopping 89 percent from its high in that market).

- If the market were to end the year at this level, it will be the second-worst year for the Dow Jones Industrials in history, behind the 52.67 percent drop in 1931. (That is not that far to go, btw.)

The knee-jerk reaction to the CPI report this morning was that prices had fallen so sharply -- the biggest drop, we're told, in 61 years -- because the economy is weakening, which is bad. Also, as prices drop, the risk of deflation rises, which is also bad. So, the 1 percent fall is bad, right?

It sure doesn't feel that way. On a consumer level, it seems great to pay less to fill up your tank, buy food and stock up on gifts and goods. There are, after all, just 35 shopping days until Christmas.

From a policymaking standpoint, lower prices offer another benefit: flexibility on rates. If the Fed doesn't have to worry about inflation, it can can continue to cut interest rates (though it is running out room). While cutting the Fed Funds rate to 0.5% would come with its own set of potentially nasty side effects, risk of stoking inflation won't be one of them.

At a time when the markets have given themselves over to federal policymakers, it's interesting to hear comments this morning from Fed vice chair Donald Kohn. Kohn says he doesn't think monetary policy can prevent asset bubbles, and he erred in believing that the Fed's response to the weakness of the early 1990s would work in other environments. It's proven to be much harder this time 'round.

Someday, when the history of this era is written, we'll know whether the extraordinary monetary-policy response to the financial crisis helped, harmed or did nothing. But, in the meantime, it's instructive to see that even the policymakers themselves aren't sure of the impact of their own hands.

A lot's been written about Jerry Yang's personal unwillingness to sell Yahoo to Microsoft earlier this year, but the board of directors shares some of that criticism. Now comes a chance for the board to either try to redeem itself or confirm that its head remains firmly in the sand.

Yang has said he will step down as CEO once a successor is found. Now the focus has to be on what type of executive the board chooses. Is it someone who can repair the strained relationship with Microsoft and get some deal together to boost shareholder value for Yahoo, or will it be someone who, like Yang, believes that Yahoo can go it alone? In short, by voting for a new CEO, the board will also be voting whether to potentially put Yahoo up for sale.

One thing is clear: Yang's decision not to run into Microsoft's arms has cost Yahoo shareholders dearly. Microsoft offered $31 a share. Yahoo closed Monday at $10.63. Yahoo shares are looking to rise Tuesday on news of Yang's resignation. If that isn't a clear sign for the board of what direction the shareholder base wants to pursue, I don't know what is. This time, perhaps, the board will listen.