Edited by CHRISTOPHER C. WILLIAMS

THE PLUS-SIZE APPAREL MARKET IS GETTING, well, bigger. As Americans' waistlines expand, so are the coffers of retailers that offer women plus-sized jeans, shirts, skirts and lingerie.

This market grew 9%, to $19.1 billion, in the 12 months ending March 2006, says research firm NPD Group. That trumped total women's apparel, which increased at a 5.2% clip. NPD says the plus-size market (sizes 14-24) is outpacing all other segments of the apparel industry and should expand by 5%-8% annually over the next five years.

The big numbers have caught Wall Street's attention. Shares in United Retail (URGI), which owns the Avenue brand of stores, have soared over 175% to about $14.50 in the last 12 months. But Erin Moloney of Merriman Curhan Ford says the stock is still "a compelling buy," trading at just 0.5 times sales.

Michael Kaplan, 33, a great grandson of Lena "Lane" Bryant, who pioneered the plus-size market more than 100 years ago, is taking a stab at the market himself. He and his older brother, Nicholas, recently launched Fashion To Figure, a store selling women's apparel sizes 14-26.

Private equity investors are getting into the act, too. Two years ago, boutique Trimaran Capital bought Secaucus, N.J.-based Urban Brands, which operates the 170-store Ashley Stewart chain, seller of plus-size women's clothing in major U.S. cities. Trimaran executives declined to discuss its plans for Urban.

An initial public offering wouldn't be a shock, given the outsized gains of the stocks. Charming Shoppes (CHRS), which owns the Lane Bryant stores, is up 27% in 12 months.

Try that on for size.

-- Jennifer Ablan