Numbers

1.77 Newborn-mortality rate per 1,000 babies delivered by voluntary caesarean section, according to a study of 6 million U.S. births

0.62 Newborn-mortality rate per 1,000 vaginal births

29.1% Percentage of U.S. births by C-section in 2004, up from 20.7% in 1996

163 Page from the hardback book A Million Little Pieces, by James Frey, that consumers must submit, with a receipt dated Jan. 26 or earlier, to get a $23.95 refund

$2.35 million Restitution--in refunds, legal fees and charitable gifts--Frey, who made up portions of his best-selling memoir, and his publisher, Random House, will pay

24% Commission the IRS will pay private collection agencies for recovering unpaid taxes

$345 billion Estimated unpaid federal taxes in 2001, the last year for which data are available

1,844 Dinosaur species that ever existed, as estimated by a University of Pennsylvania paleontologist and a Swarthmore statistician

527 Number of dinosaur species that have been discovered so far

$250,000 Cost of a fully implantable artificial heart approved last week by the FDA for use in up to 4,000 people with severe congestive heart failure

2 lbs. Weight of the device, which makes it an option only for men and large women

5.2 Average number of months the first 12 recipients survived with the device

Sources: New York Times (5); USA Today; Washington Post; Philadelphia Inquirer (2); Wall Street Journal (2)