Pure Plays

Q What's a "pure play" company? — M.J., Tucson, Ariz.

A Unlike conglomerates, a pure play is a company that focuses on one single business. When investors are drawn to a particular industry, they may look for a company that's a pure play, so their invested dollars won't be spread out over other, less desirable businesses.

If your research suggests that the lightbulb industry is one of the most attractive and profitable ones around and you want to invest in it, you might invest in General Electric, which makes everything from lightbulbs to airplane engines. Or you might try to find a pure-play lightbulb company. The hypothetical Bright Idea Lightbulb Co. (ticker: UREKA) might fit the bill. Funds in UREKA would be focused solely on lightbulbs, while GE also makes everything from security systems to NBC to aircraft engines, with each operation having varying profitability characteristics.

Coca-Cola is a beverage pure play, unlike PepsiCo, which has a giant snack operation in Frito-Lay. Barnes & Noble is a bookselling pure play, while Amazon. com sells books and much more.

Q Where can I go to figure out how much inflation has occurred within a certain time span?

— B.C., Midland, Mich.

A click over to the Web site of the Department of Labor's Bureau of Labor Statistics and you'll find a handy inflation calculator: http://data. bls.gov/cgi-bin/cpicalc.pl. If you want to know how much buying power $100 in 1970 would have today, just ask. The answer: $564. (Another good calculator: www.westegg.com/inflation.)

To learn the average inflation rate over a period, visit www.measuringworth. com/growth andselect "Consumer Price Index." (From 1977 to 2007, it was 4.2 percent.)

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