Numbers: Jul. 23, 2007

FINANCES

$15 trillion

Estimated assets held by Americans 65 and older, the most in history for that age group

30%

Percentage of Americans 65 and older who say they don't have enough money to meet their basic living expenses

WEATHER

116°F

Temperature in Las Vegas on July 5, tying the record set on that date in 1985

30

Number of U.S. states facing a drought as of July 5

AERODYNAMICS

50%

Proportion of the primary structure of Boeing's new Dreamliner aircraft, unveiled on July 9, that is made of carbon fiber and other composites instead of aluminum. The new materials reduce the weight of the plane

20%

Percentage by which the design of the Dreamliner will reduce fuel usage compared with similarly sized planes. Claims for the jet's main rival, the much larger Airbus A380, also include an environmental edge: by ferrying more passengers, it can reduce congestion and emissions in the skies

REAL ESTATE

$165 million

Asking price for a Beverly Hills, Calif., mansion that once belonged to publishing magnate William Randolph Hearst. It is believed to be the most expensive U.S. residential listing ever

$120,000

Approximate price Hearst laid down to buy the mansion in 1947. The 6.5-acre estate now boasts three pools, 29 bedrooms, a movie theater and a disco

Sources: Boston Globe; Pew Research Center for the People and the Press; New York Times; CNN; Advertiser (2); AP; Unique Homes magazine; AP