As the third presidential impeachment trial in American history looms, it may seem like Donald Trump is a ubiquitous presence on the national and world stages.

His tweets still generate news coverage, he can still singlehandedly move world events by ordering military actions, and his every utterance is still broadcast to the world and carefully transcribed, parsed, and analysed by a dedicated coterie of journalists.

But as the House is poised to trigger the start of Mr Trump's trial by voting to send its two articles of impeachment against Mr Trump to the Senate, data obtained by The Independent strongly suggests the president has — with limited exceptions — largely retreated from public view since Democrats launched their impeachment inquiry on September 24.

Mr Trump's work habits have long been known to differ markedly from all of his recent predecessors. He routinely starts his day later and ends it earlier than other recent presidents, with a record low of 5 hours between his first and last public engagements over the course of his term in office.

Additionally, the 45th president has broken with his recent predecessors by largely eschewing presidential press conferences in favour of informal question-and-answer sessions, known as "pool sprays", during scheduled public events and upon arriving or departing from locations.

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But data provided to The Independent by Trump-tracking database Factba.se shows that Mr Trump spends far less time in the office than his predecessors, with much of his schedule devoted to unstructured "executive time" — used for watching television, calling friends and associates, and tweeting — in the White House residence.

And since the House's inquiry into whether to impeach him for allegedly withholding $391 million in military aid to Ukraine to persuade that country's president to purse investigations into the president's political rival and a discredited conspiracy theory centred around the 2016 election, Mr Trump's public profile has become even lower.

Since the impeachment inquiry began on 24 September 2019, Mr Trump has had fewer public engagements and taken press questions far fewer times than the same time one year earlier.

For example, from 1 October to 31 December, 2018, Mr Trump participated in 57 separate question and answer sessions, more than double the number he participated in over the same time period last year.

Additionally, Mr Trump's schedule had approximately 13 per cent fewer public engagements listed in the last quarter of 2019 compared with the year before, though such a discrepancy could theoretically be attributed to 2019 being a non-election year. His public schedules have also included far more days without any events open to the press since the impeachment inquiry began. While it has continued to include the usual closed-door meetings and briefings with administration officials, Mr Trump frequently can go days without being seen by the media.

Moreover the number of days without any "official" events has jumped markedly. His schedule for this week, for example, only includes two official engagements, a signing ceremony for his "phase one" trade agreement with the China and an announcement of administrative "guidance on constitutional prayer in public schools." Other than his Monday evening trip to the US college football national championship, his two trips outside the White House this week — to a Tuesday night "Keep America Great" rally in Wisconsin and a Friday night campaign fundraising dinner in Florida — are of a solely political nature, conducted in service of his reelection campaign.

But being more frequently out of the public view does not mean that Mr Trump goes without being heard from. At the same time his public appearances have decreased, his often-pugilistic social media output has skyrocketed.

On Mr Trump's favourite platform, Twitter, the total number of tweets and retweets posted by the president's @realDonaldTrump account over the fourth quarter of 2019 was more than quadruple that of his 2018 output during the same period.

From 1 October through 31 December of last year, the president or his staff pressed "tweet" or "retweet" 3,286 times, compared with 736 times the prior year.

Data compiled by Faceba.se makes clear that the House's impeachment proceedings were the driving force behind such prodigious increase. On the day the House Judiciary Committee debated two articles of impeachment against him, Mr Trump tweeted or retweeted 123 separate pieces of content, breaking the record of 105 tweets and retweets set four days prior.

Similarly, over the 24 hours spanning the day of the House's vote to approve both articles of impeachment against Mr Trump and the day after, he tweeted or retweeted content a total of 144 times.

Mr Trump's frequent comments on impeachment and his relatively light public schedule are a marked contrast from that of the last American president to face a senate trial.

During the 1998-1999 impeachment of then-president Bill Clinton, Mr Clinton's aides kept their boss as busy as possible and made sure he was seen doing the people's business, rather than sulking over becoming the first impeached president of the modern era.

"Most of [Clinton's] days looked like they had before impeachment," said Joe Lockhart, who served as Mr Clinton's press secretary from 1998-2000.

Top aides to Mr Trump insist that he is hard at work almost constantly. When asked about the dearth of public events on his calendar, Counselor to the President Kellyanne Conway told The Independent that "it doesn't feel like" Trump has reduced his work schedule in any way.

But when asked about Mr Trump's meagre number of public engagements, Mr Lockhart told The Independent that in Mr Clinton's time, it would have been nearly unheard of for the president to not be seen by the public to be putting in a full work week.

The fact that he'd been impeached never made much of an impact on his daily schedule, Mr Lockhart explained.

"There'd be some big message event and then a series of smaller events that the press would cover, then he did lots and lots of policy meetings," Mr Lockhart added. "It was what, up until this point, being president looked like".

The Clinton team's efforts to keep their president on message were aided by the fact that, unlike Mr Trump, Mr Clinton did not have a television easily accessible to him, a stark contrast with Mr Trump's White House, in which televisions simultaneously displaying four news channels are ubiquitous.

(Mark Wilson/Getty)

The goal of Mr Clinton's packed schedule and reticence on the subject of impeachment, Mr Lockhart explained, was to keep the president of the United States from looking forlorn or self-pitying.

"The biggest danger posed [by impeachment] was becoming or looking like a victim and putting yourself in front of the country's interest," he said, because doing so would have been "political death".