The 60-vote threshold and filibuster threat are treated as the gospel these days in the U.S. Senate. But columnist Paul Krugman noted they are recent creations. He wrote: "The political scientist Barbara Sinclair has done the math. In the 1960s, she finds, 'extended-debate-related problems' — threatened or actual filibusters — affected only 8 percent of major legislation. By the 1980s, that had risen to 27 percent. But after Democrats retook control of Congress in 2006 and Republicans found themselves in the minority, it soared to 70 percent." Krugman concluded that "nobody should meddle lightly with long-established parliamentary procedure. But our current situation is unprecedented: America is caught between severe problems that must be addressed and a minority party determined to block action on every front."