Explain to me: Why are we talking about Trump's tax returns again?

On their own, the words ‘Donald Trump’ and ‘tax return’ could put you to sleep faster than a general anaesthetic.

Yet for what seems like 100th time in the last few months, we’re back talking about Trump and his taxes.

So how did we get so enthralled by a two-page document dating back to 2005, and what the hell is really going on? Here’s a really basic rundown of everything that went down, and why it matters (or perhaps doesn’t).

Let’s rewind and go back to the very start

OK, so Trump has always been a little weird about his tax returns. In fact, he is the first Presidential candidate – Democrat or Republican – to not make his financial records public since 1976.

Rumours have flown and speculation rife about why Trump has been so hesitant to open his tax returns to the public. Was he actually just very broke? Would it show he had some funky dealings with Russia along the way? Had he been chronically rorting the American tax system for decades?

According to Trump himself, he was unable to release the returns because of an audit by the Internal Revenue Service. (The IRS is a U.S. government agency responsible for tax collection and tax law enforcement.) The IRS denied this, and according to News Corp, said there was no reason why Trump couldn't release his tax returns.

As tends to happen with conversations about Trump, confusion swirled for months before everyone got a little bit tired of reaching dead ends.

But that didn't mean the issue didn't annoy the public. In a poll conducted by ABC News and The Washington Post in January, almost three-quarters of Americans wanted Trump to release his tax returns.

So why are we talking about them now?

On Tuesday at 7.36pm New York time, MSNBC news anchor Rachel Maddow set the political world ablaze when she announced before her 9pm show that she was set to reveal unseen tax records from President Trump.

For lack of a better word, Twitter went nuts.

The records were provided to the MSNBC by Pulitzer-prize winning journalist David Cay Johnston, who said a two-page copy of Trump's 2005 tax return was "left in his mailbox".

So did they actually show anything?

Um, not really.

The two-page document shows Trump paid roughly US$38 million in taxes on US$150 million in income that year. If we do the maths, that means in 2005 Trump paid an effective tax rate of around 24 percent. Which, you know, is better than nothing.

As it stands, the figure isn't a bad one. According to The Columbus Dispatch, who looked at data from the Congressional Joint Committee on Taxation, 24 per cent is well above what the American taxpayer forks over each year in tax (around 10 per cent).

However, it's below the 27.4 percent taxpayers earning one million dollars a year on average pay. So that's a little bit questionable.

More interestingly, though, is a revelation the former businessmen had to pay tens of millions of dollars of tax in one year because of a tax rule he has specifically promised to abolish as president. It's called the “alternative minimum tax” or the AMT.

Without getting too bogged down in the numbers, US$31 million of the tax Trump paid in 2005 was because of the AMT. He actually only paid US$5.3m in regular federal income tax. So it's little wonder it's a rule he wants to get rid of; it's a proposal that, at least in 2005, could've reduced his effective tax rate from 25 percent to just 4 percent.

You don't need me to tell you that that's a lot of monies.

How did the White House respond?

The Trump administration hit out at Maddow before her 9pm show had even aired on Tuesday (or 12pm AEDT on Wednesday).

“You know you are desperate for ratings when you are willing to violate the law to push a story about two pages of tax returns from over a decade ago,” the White House said in a statement.

“The dishonest media can continue to make this part of their agenda, while the President will focus on his, which includes tax reform that will benefit all Americans.”

So there's that.

Listen: Mamamia Out Loud on why it’s time to stop shouting and start trying to understand the people we don’t agree with. (Post continues after audio.)

Is that it?

Generally speaking, yes, but there are a few other interesting points to be made.

There's much speculation Trump may have leaked the documents himself. According to Johnston, "it's entirely possible" it was Trump who sent him the documents.

"It's a possibility, and it could have been leaked by someone in his direction."

Another factor that hints to Trump's involvement is that the tax return in question was labelled "client copy," indicating it came from someone close to him rather than the IRS or an accountant.

After all, it was a pretty boring tax return. There wasn't a lot in it, and it did prove, in one way or another, that at some point he did pay some tax. As some have pointed out, it may well have been the most tax he's yet paid, and exactly the reason he may want this specific return the one that's public.

But then on the other hand - why bring this back into public conversation? And perhaps more importantly, the fact the rest of his tax returns remain to be seen is something likely to keep the public hot on the President's tail for a while longer.