The fact that the United States government is deeply divided across party lines is no surprise, especially to anyone who watched Democratic representatives recently camp out on the House floor for the better part of a day to protest Congressional inaction on gun control (via Periscope, since Republican House Speaker Paul Ryan had declared a recess and shut off C-SPAN cameras). 

But just how divided is Congress? Last year, a group of researchers looked into cooperation and partisanship in the U.S. House of Representatives over the last 60 years, comparing networks of agreement on legislation in the House between 1949 and 2012. The study (as unearthed by Business Insider) was published in the journal PLOS ONE.

Compare the links between representatives in the '50s to the early 2000s:

As the graphic shows (Business Insider has an animation that helps break it down in more detail), Congress has, in fact, been growing ever more divided. There are fewer connections (representing agreements on votes) in the 2000s than there were in earlier decades. 

This disagreement comes at a cost. A more divided Congress gets less done, as the researchers point out (and the recent standoffs over gun control in both the House and the Senate show). “This is particularly apparent in the steady reduction of the number of bills introduced onto the floor, suggesting that the primary negative effect of increasing partisanship is a loss of Congressional innovation.”

Just look at the network for 2005—a year when Congress met so few times that it surpassed even the "do-nothing Congress" of 1948.

[h/t Business Insider]

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