CHICAGO - While overall beer sales are falling, seasonal beers are becoming an increasingly attractive segment for the country??s largest brewers, the Chicago Tribune reports.

Seasonal beer sales have posted dollar sales increases of 15% to 26% for each of the last three years, according to SymphonyIRI, a Chicago-based market research firm. Most recently, seasonal beer sales for the year ended March 18 among grocery, liquor and convenience stores totaled $245 million, an 18% rise from the previous year (the data excludes sales from Walmart, clubs stores, bars and restaurants).

"Customers see (seasonal beer) as something new and fresh," prompting them to think "I'd better try it before it goes away," said Craft Brewers Association Director Paul Gatza.

Seasonal beers are typically lighter in color and flavor during spring and summer and heavier during winter and fall.

Boston Beer Co. founder Jim Koch said he isn??t surprised at the popularity of seasonal beers, and his company??s Sam Adams brand has been capitalizing on the appeal for many years.

"It's become a popular thing in the last three to four years" in the industry, Koch said, adding that he's been making them for a quarter-century. "It's grown to be a bigger piece of the business."

Chicago-grown Goose Island Beer Co. has increased its seasonal production since being acquired last year by Anheuser-Busch.

"Our growth in seasonals has continued every year and continues to grow," said Goose Island brand director Adam Lilly. Seasonal sales increased 22% last year compared to 2010.

Gatza said seasonal are one of several ways large brewers are looking to grab space from craft brewers, which were the original makers of seasonal beers.

"We're seeing more (research and development) by large brewers," Gatza said. "They're trying to expand in as many directions as possible, but there's a limited amount of shelf space, so if there's a new product on the shelf, something else is going to lose a spot."

Read more on the growth of craft beer in convenience stores in the March NACS Magazine feature "Untapped Potential."