PITTSBURGH (AP) — Private landowners are reaping billions of dollars in royalties each year from the boom in natural gas drilling, transforming lives and livelihoods even as the windfall provides only a modest boost to the broader economy.

In Pennsylvania alone, royalty payments could top $1.2 billion for 2012, according to an Associated Press analysis that looked at state tax information, production records and estimates from the National Association of Royalty Owners.