“Bipartisanship” is a weird, malleable word in the context of Senate legislation. Does it mean a bill that earned votes from a number of senators from each party? At least one vote from each? A bill that most Americans support? A bill that was drafted with input from members of each party? Everyone seems to agree that bipartisanship is ideal but, because of that, everyone also seems to reorient it in a way that’s particularly useful at a particular moment.

So we have Senate Minority Leader Mitch McConnell (R-Ky.) firmly proclaiming on Tuesday that “the era of bipartisanship is over.” The occasion was apparently another collapse in conversations between the White House and Republicans over an infrastructure package, legislation that both President Biden and Democratic senators such as Joe Manchin III (W.Va.) hoped would be in some form bipartisan. Again, what standard needed to be met was never clear. It’s like the old “know it when you see it” standard about porn, except for the polar opposite of porn, which is a congressional funding bill for highways.

As soon as McConnell made those comments, you could hear eyes rolling from the offices of Democratic senators. In part because of Biden’s repeated declarations that he wanted legislation to be bipartisan, McConnell has made few overtures to actually meet the Democratic mini-majority on legislation. In fact, he said last month that “100 percent of our focus is on stopping this new administration,” which isn’t particularly “bipartisan” as an outcome.

If that comment sounds familiar, it’s because McConnell said something similar shortly before the 2010 midterms: that the “single most important thing we want to achieve is for President Obama to be a one-term president.”

The question, then, is this: If the era of bipartisanship is over, when did it actually exist? Is McConnell saying that it’s over the way one might say the age of the dinosaurs is over, as a statement of fact not a declaration of a change in status? Or is he actually arguing that there was some bipartisanship going on until this week?

Because “bipartisanship” is so squishy as a term, it’s also hard to measure. To do so, I determined the frequency that any given number of affirmative votes was cast for legislation, nominations or clotures — motions to end a filibuster — in each Senate since McConnell became the leader of the Republican caucus. The idea was this: An era of bipartisanship should see more affirmative votes than the number of senators in the majority, using a definition of “bipartisan” that includes earning votes from one’s opponents.

Here are those data. It’s a complicated graph, so I’ll explain a bit below.

The peaks represent the percentage of votes cast at every yes-vote range from 0 to 100. So if most of the votes cast yielded 50 affirmative votes, the column at 50 would be higher than the rest.

There are two particularly interesting horizontal ranges. The first is the stretch from 50 to 60 votes, the points at which a piece of legislation might pass to the one at which a filibuster can be overcome. You’ll notice that there are a lot of cloture votes in this range; filibusters are a useful way for the minority to block legislation when the majority has fewer than 60 votes in its caucus, the margin needed for cloture.

A lot of the cloture votes, though, also land at the other interesting range, the near-unanimity part of the graph. Sometimes everyone just agrees to end a filibuster, and sometimes (not very often) everyone agrees to support legislation.

Because the actual majorities shift from Congress to Congress (and year to year, thanks to retirements and deaths), we need to contextualize the vote tallies relative to the number of votes held by the majority party. So I figured out the percentage of affirmative votes cast each year relative to the size of the majority at the start of the year. In 2021, for example, nearly half of the cast votes have resulted in between 47 to 53 affirmative votes — a margin of three votes on either side of the Democrats’ 50-vote majority.

If we extend that same window backward, you see that the lack of partisanship this year has, in fact, been unusually high. But also that it has been increasing since about 2013, when Obama began his second term in office.

You can see this effect in that first graph, too. It’s hard to pick out the number of votes that were most common that year because the votes were pretty evenly distributed across the spectrum of possibilities. By 2013, though, it was easier to see where most votes landed; that year, it aligned with the size of the majority Democratic caucus.

Again, this is a rough way of looking at a nebulous concept. But it does seem to reinforce what most Americans probably felt in their guts: The idea that the era of bipartisanship in the Senate just ended seems to depend an awful lot on not having any idea what the Senate was doing before about two months ago.