In the latest numbers from Gallup, just sixteen percent of Americans approved of how Congress is doing its job. The reaction of the political world? Ho-hum. After all, everyone knows that the public hates Congress — and always has.

Except that they haven’t.

In fact, as recently as 2005, Congressional approval regularly hovered around 40 percent — not exactly high enough to win any popularity contests but nowhere near the used car salesman/reporter level where it currently resides.

In fact, only twice between 1974 and 2005 did Congressional approval dip below 20 percent — once in 1979 and once in 1992. Since February 2005, however, Congressional approval dropped below 40 percent and has continued its downward descent ever since.

Just to be reiterate: In 30 years of polling data Congressional approval dropped below 20 percent a total of twice; since 2005 it hasn’t been over 40 percent once and has averaged — yes, averaged — 17 percent since 2010. (Sorry for all the italics. But, wow.)

What gives? Why did a modestly unpopular institution turn into a hated one over the past seven years?

Theories abound.

Former Rep. Tom Davis (R), who left the House in 2008, argued that Congress has shown little ability to get things done and, when they have done something, it’s proven to be unpopular.

“Congress has produced nothing but bad outcomes,” said Davis. “Two failed wars, stagnant wages [and] economic meltdown”

A look back at the last seven or so years of Congressional action/inaction proves Davis’ point. Among the high/lowlights: the failed attempt to overhaul Social Security, the Jack Abramoff lobbying scandal, the Mark Foley page scandal, the Troubled Asset Relief Program (TARP), the healthcare slog, the budget showdown, the debt ceiling fight and the failure of the supercommittee.

That’s a murderer’s row of bad news and embarrassing moments that would lead any thinking person to conclude that Washington is not only broken but that the very people elected to fix it have no clue of how to do so. (Make sure you read Ezra Klein’s riff on why this is the worst Congress ever.)

And, unlike in the ‘70s, ‘80s or even ‘90s, the growth of things like 24- hour cable news, You Tube and Twitter (among many other mediums) mean that more minor problems/scandals/issues relating to Congress now get major league attention — further eroding public confidence in the institution.

“All that information produces opinions about who you support and who you don’t,” said former New York Rep. Tom Reynolds (R). “Intense dislike for those you don’t support and opinions you are opposed to appear to run deep in an almost equally divided electorate.”

And then there is the broader cultural context in which Congress has operated over the past seven years — a period of heightened economic anxiety, a re-thinking of America’s rightful place on the world stage and a questioning of longtime pillars of our society (government, banks, media etc.) that has made pessimism the default position of the country.

“My instinct is that people are more forgiving of Congress when they have a job and those that have jobs feel secure in them,” said former Texas Rep. Chet Edwards (D), who, added, however, that the uncertainty people are feeling can't solely be blamed for Congressional unpopularity.

Any time an institution as venerable as Congress experiences a drastic change in public perception, no one thing deserves the credit/blame. Congress’ lack of meaningful accomplishments, the wall-to-wall coverage of its failures and the country’s negative bent have all combined to drive down the approval number of the House and Senate.

Regardless of the reasons, however, don’t make the mistake of assuming Congress always has been this unpopular. Because it hasn’t. In the past seven years, Congress has made history — and not the good kind.