It's no secret how much the craft beer industry has exploded over the last several years, especially in Grand Rapids. We are this year's BeerCity USA after all. One of the early craft beer advocates has been rewarded handsomely with the industry's growth. Samuel Adams beer founder Jim Koch now joins the billionaire club thanks to the rise in his company's stock.

According to NPR, Sam Adams stocks rose dramatically since July, when parent company Boston Beer Co. reported a net revenue of about $181.3 million. This makes Koch's net worth at about a billion dollars. Earlier this week Boston Beer stock was priced at about $227, a far cry from $20 a share in 2009.

Koch has seen the highs and lows of Sam Adams since he founded the brand in 1984. "Having watched my stock price go up and down and up, it seems almost whimsical," the sixth-generation son tells Bloomberg. "I remind people getting rich is life's great booby prize. Any normal person would much rather be happy than rich."

Sam Adams is the official sponsor of GRD's first annual Oktobeerfest September 21 at The Intersection. Sam Adams beers that will be available at the event include Oktoberfest, Fat Jack Double Pumpkin, Grumpy Monk and Hazel Brown.

Tickets are just $10 in advance, which includes a glass beer boot, and on sale at the Intersection box office and here.

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