It won’t surprise you to learn that the past few years have been the most politically polarizing in the last half century. Lots of partisan snarling and snapping through the Bush/Obama years what with foreign wars, the Great Recession, immigration, gay marriage, health care insurance, government shutdown, and such like.

But the Gallup polling organization has put some numbers to the trend – a sort of low mark against which the newly-Republican Congress and the lame-duck Democratic president can work toward some semblance of bipartisanship as they deal with a plateful of important issues as well as the approaching 2016 elections.

“Each of Obama’s six years in office rank among the 10 most polarized in the last 60 years, with George W. Bush holding the other four spots,” writes Gallup’s Jeffrey M. Jones. “Bush’s most polarized years were his fourth through seventh years in office, after the rally in support for him following the 9/11 terror attacks had faded. Clearly, political polarization has reached new heights in recent years, under a Republican and a Democratic president.”

“Polarization” here is measured by the partisan gap in approval ratings.

In Mr. Obama’s sixth full year (Jan. 2014-Jan. 2015), for example, he averaged a 79 percent approval rating among Democrats and just 9 percent among Republicans. That 70-point gap wasn’t the worst for Obama. The average party gap in 2012 was 76 points (86-10).

Mr. Bush’s approval gap in his fourth year as president was also 76 points (91-15). For his total time in the White House, Bush’s average approval gap was 61 points – far higher than his father’s (38 points) during George H. W. Bush’s single term in office.

“Not surprisingly, Bush and Obama had by far the most polarized sixth years for presidents who served into a sixth year,” writes Mr. Jones. “In Bill Clinton’s sixth year, there was an average 53-point gap in his approval ratings, 17 points lower than those of his immediate successors…. The other presidents serving into a sixth year had polarization scores below 50 points – including Dwight Eisenhower and Ronald Reagan, who were popular at the time, and Richard Nixon, who had historically low approval ratings. Nixon resigned in August 1974, in the middle of his sixth year in office.”

It’s not just polarizing issues like wars dragging on and Obamacare, Gallup’s Jones suggests. Here, he cuts Obama a bit of slack.

“These increasingly partisan views of presidents may have as much to do with the environment in which these presidents have governed as with their policies, given 24-hour news coverage of what they do and increasingly partisan news and opinion sources on television, in print and online,” he writes. “Operating within this context, Obama is on pace to be the president with the most polarized approval ratings in Gallup’s polling history, surpassing Bush.”

One likely result of this polarization: the number of self-declared Independents has climbed to a record 43 percent, the highest number since Gallup began tallying such figures  back in 1988 – leaving Democrats and Republicans trailing far behind at 30 percent and 26 percent respectively.

In another report out Friday, the pollster ranked the most conservative and most liberal states.

Mississippi, Alabama, and Louisiana are the most right-leaning states in the union, with between 46 percent and 49 percent of residents in each identifying as politically conservative, Gallup reports. Massachusetts, Vermont, and Hawaii are the most left-leaning, with 30 percent of residents in each of those states identifying as liberal. In general, the rankings haven’t changed much since 2008.

“Six of the top 10 most conservative states are located in the South (Mississippi, Alabama, Louisiana, Arkansas, Tennessee and South Carolina). Three others are in the Mountain West (Utah, Wyoming and Idaho), and one is Oklahoma – straddling the Midwest/southern border,” writes Frank Newport, Gallup’s editor in chief. “The top 10 liberal states are primarily located in the outer longitudes of the U.S.: touching or close to the Atlantic Ocean (Vermont, Massachusetts, Connecticut, New York, New Jersey and Maryland), and the Far West (Oregon, California, Washington and Hawaii).”

The state with the greatest number of self-identified moderates? Delaware.