The week's blistering stock sell-off has slashed the Dow Jones Industrial Average's gains since President Donald Trump's election.

What was once a 61% Dow gain just 16 days ago on Feb. 12 has eroded to a far thinner 38.6% rally as the index fell from an all-time high of 29,568 to around 25,409. The gain in the Dow is just 28.8% if you measure from Trump's inauguration day more than three years ago.

These calculations measure the percent price change of the Dow over a given period and exclude fixed returns like dividends.

The dramatic fall in Dow (and S&P 500) gains since the president's election came after the single worst week on Wall Street since the financial crisis.

For the week, the Dow fell more than 3,500 points, or 12%, in its biggest weekly percentage loss since 2008. The blue-chip index ended the week firmly in correction territory, down more than 14% from its record close notched earlier this month.

The S&P 500 lost 11.5% over the week and, as such, also clinched its worst weekly performance since the crisis and closed in a correction. The typical correction sees the S&P 500 fall 13.7% and usually takes four months to recover.

Despite the hefty near-40% gain Trump still has, he is irate at the sell-off, according to CNBC sources. The stock market is falling amid growing concerns over the coronavirus and its potential impact on the global economy.

The president blamed both the threat of 2020 Democratic candidates as well as the coronavirus for the week's steep declines. The president said on Wednesday that he believes "quite a bit" of the sell-off was thanks to investor fears over Democratic candidates' radical economic and policy ideas expressed during this week's debate.

"I think [investors] look at the people that you watched debating last night and they say 'if there's even a possibility'" a Democrat is elected the economy will decline, Trump said on Wednesday. "I think the financial markets are very upset when they look at the Democrat candidates standing on that stage making fools out of themselves."

The president even went so far on Friday as to categorize the criticism of his administration's response to the disease a new "hoax" cooked up by Democrats hoping to oust him from office in the 2020 presidential election.

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