MUNCIE, Ind. -- The days of the general merchandise store are long gone and so is the concept of the same merchandise being purchased by everyone, says a Ball State University retail analyst.

Retailers have attacked the consumer market with a vengeance, dividing segments by household income and social class, and offering specially-priced merchandise to each group, said James Lowry, a marketing professor.

"You can't assume that you can manufacture one item and it will meet the needs of every income or social group," Lowry said. "Jeans are a great example. A company might offer a special, high quality denim jean with a special logo for about $60 at a fashion mall, and then sell a similarly-designed but lower quality pair of pants for about $20 at Kmart.

"To sell the most products, you have to offer merchandise that a particular group can afford," he said. "Then, you allow consumers to vote with their pocketbooks."

Lowry believes that in the 1990s manufacturers and retailers finally gave up on the general, all-purpose line and switched to multi-tier marketing.

This is a major shift in thinking. Before, manufacturers believed the premise that any product could be sold to the masses if it were properly packaged and hyped, he said.

Helping to shift the paradigm is the loss of purchasing power for America's middle and lower income families. Since the 1980s, the wealthiest 20 percent of America's population has seen its income grow by 21 percent.

This group now accounts for 54 percent of all new car purchases, up from 40 percent in 1980. It is estimated that millionaires will control 60 percent of the nation's dollars in 2005, according to the Affluent Market Institute.

"In the last few years, we've seen a whole new group of wealthy and upper individuals created through the information technology revolution and the stock market boom," Lowry said. "These people have a great deal more discretionary income after they pay for housing, food and other basic living costs.

"This group is able to afford the more expensive homes, the sport utility vehicles and fashionable clothes," he said. "The rest of the population is being serviced by discounters that offer satisfactory quality merchandise at a lower cost."

While the upper income class has expanded, wages for the bottom 60 percent of America's population have stagnated or shrunk. About 100 million people -- or 40 percent of the U.S. population -- live in households earning between $35,000 and $75,000 yearly.

Discount stores such as Kmart, Wal-Mart and Target are booming because they offer their customers -- usually the middle and lower income groups -- quality goods at low prices, Lowry said.

"For the wealthiest people, you'll develop a line that is very high quality with all the bells and whistles," Lowry said. "For the middle income group, you will have a very functional product. And, for the lowest income groups, the product becomes simply functional without being anything fancy -- meeting their basic needs."