Here's the truth about President Obama's job approval numbers: They don't move around all that much.

President Obama

New numbers from Pew Research Center tell that story.  Forty nine percent of respondents approved of the job President Obama while 43 percent disapproved.  Those numbers are remarkably unchanged from where Obama stood in a January Pew poll despite the fact that the past five and a half months have seen the failure of the White House's attempt to change gun laws, the IRS scandal, evidence of an improving economy, the NSA revelations and plenty of other "major" news events.

The Pew numbers are broadly in keeping with the large majority of polling data released over the last few months including Washington Post-ABC News surveys.

Here's a look at Obama's job approval in Post-ABC polling since 2009:

Since mid-2011, Obama's job numbers have fluctuated marginally (if at all), with the lone exception being a post 2012 re-election bid bump he received in Post-ABC polling -- and virtually every other poll too.

The truth is that for every poll that shows significant fluctuation in Obama's job approval numbers -- like the CNN survey earlier this week that showed Obama down to 45 percent approval -- there are three (or more) that show no real movement.

And, there's a very simple explanation for why Obama's numbers don't move all that much. It's partisanship.

Check out these numbers from Post-ABC polling on Obama's job approval by party.

At least 80 percent of Republicans disapprove of the job President Obama is doing. At least 80 percent of Democrats approve of it. Independents are almost evenly split on the question. That's true regardless of any external events -- small or large. Remember how the capture and killing of Osama bin Laden would fundamentally alter how people viewed President Obama? That lasted about a week. Or how the IRS scandal would doom Obama's second term approval ratings? Not so much -- or at least not yet.

What the numbers tell us is that anyone with even an inkling of partisanship has been pushed into one of the two parties at this point. Of the ten most polarized years -- defined by the difference in presidential approval between adherents of the two parties -- in history nine of them have come during the presidencies of George W. Bush and Barack Obama.

Minds are made up -- both for and against President Obama. His polling ceiling and floor are very defined and, at least based on the last few years, largely unaffected by external circumstances. Given all of that, large-scale changes in how the public perceives Obama is very, very unlikely -- now or at any time until he leaves office in early 2017.