President Obama recently called the massive oil slick spreading in the Gulf of Mexico a "potentially unprecedented environmental disaster." The situation is so dire, comparisons to Hurricane Katrina have become commonplace. To get a sense of the magnitude of the spill's damage and cost—and how much worse it could get—here are some salient facts and figures:

11 million
Size in gallons of the Exxon Valdez oil spill—until now, the worst in U.S. history

12.2 million
Size, in gallons, of the BP spill as of May 1, according to one estimate from an oceanography professor at Florida State University

Days it will take to cap the leak, according to many estimates

1 of 3
Number of leaks patched, as of May 6

Weight, in tons, of the four-story concrete-and-steel bell BP is deploying to stop one of the larger leaks

1 million
Gallons per day of oil currently leaking from the sunken BP rig, according to industry insiders

94 million
Ultimate size of spill, in gallons, if that rate continues for 90 days

6.8 million
Gallons per day BP predicts could begin gushing out of the well in the "worst-case scenario" of a complete "blowout" at the sunken rig

378 million
Total spill size, in gallons, if this "worst case scenario" leak rate were to continue for 90 days—or 34 times the size of the Valdez spill

Animal species put in harm's way by the spill

Dead sea turtles already found washed up on shore

Estimated size of the oil slick, in square miles, on April 29

Estimated size of the oil slick, in square miles, on May 5 (the latest such estimate)

Square miles of federal fishing areas in the Gulf that have been closed due to the slick

Percentage of U.S. shrimp production that comes from the Gulf Coast

$75 million
Limit on what companies have to pay to cover damage from oil spills (if they're not at fault), under federal rules

$10 billion
The new liability limit under the proposed "Big Oil Bailout Prevention Act" in Congress

$7 billion
Cost of the Exxon Valdez spill

$14 billion
Current estimated cost of the BP spill

$300+ billion
Estimated cost of the spill in a worst-case scenario, according to a top financial analyst

$20 billion
BP's loss in market value, following a 13 percent plunge in its stock price

$163 billion
BP's total profits between 2001 and 2009

$6 million
Amount BP has been spending per day on the spill

Number of people directly involved in the effort to stop the leak and contain the damage, as of May 5

Number of ships and other seafaring vessels involved

Depth, in feet, of the wellhead and the sunken rig

Depth, in feet, of the oil reservoir

The number of other oil wells in the Gulf, according to Interior Secretary Ken Salazar

(This story was last updated on May 6)

Sources: Reuters, AP (2, 3), Wikipedia, Washington Post, New York Times, L.A. Times, AP, KWTX, CNNMoney, CNN, Denver Post