Matt Krantz

USA TODAY

It's been an ugly stock market for most investors. But famed inventor and investor Elon Musk is having an exceptionally bad year - not just on one investment - but on two.

Musk's holdings in electric car maker Tesla (TSLA) and solar panel installer SolarCity (SCTY) are down a staggering $3.5 billion since the end of last year on Dec. 31, 2015. Musk is the largest single owner of both companies, which together have handed all investors total market value losses of $15.7 billion this year.

Musk got some relief Wednesday. Tesla shares jumped 10% in early afterhours trading, after it gave fourth quarter results and said it will turn a profit this year. But the damage is already done - even if the 10% gain sticks, Musk's loss on the two stocks this year would be $3 billion.

Both of Musk's firms have lost favor with investors this year, as the market punishes companies that are thin on profit but high on valuation. Falling oil prices have also taken out the urgency and enthusiasm over alternative energy plays.

Musk is now down $682 million in his shares of SolarCity this year. The stock plunged 29% Wednesday to $18.63 after the company that installs and leases solar panels told investors late Tuesday it will likely lose up to $2.65 a share in the current quarter. That's deeper than the $2.49 a share loss investors were expecting, according to data from S&P Global Market Intelligence.

The negative outlook completely overshadowed the fact that during the fourth quarter the company reported a better-than-expected quarterly loss of an adjusted $2.37 a share. Shares of SolarCity were already down 48% this year - before Wednesday's drop.

Next, all eyes are on Musk's big investment: Tesla.

Musk's massive $4.2 billion stake in Tesla makes his $404 million position in SolarCity look minor.

Shares of Tesla are down 40% this year through Wednesday's close - serving up a nearly $12 billion loss to investors - of which Musk has personally eaten $2.8 billion. After the market closed Wednesday, Tesla reported a quarterly loss of 87 cents a share on an adjusted basis. Investors thought the company would turn a profit, reversing four-straight quarterly losses, says S&P Global Market Intelligence.

His stakes in SolarCity and Tesla are still valued at $4.6 billion. That doesn't even include Musk's stake in space flight pioneer SpaceX, which is privately held.

Perhaps Tesla's profits can turn on the turbo later this year - as it said late Wednesday it would - and blow away the negative investor sentiment. But so far, investors who have gotten hammered this year betting on Musk - including Musk himself.

ELON MUSK'S ROUGH YEAR

Company, symbol, % ch. YTD, Musk's paper loss

SolarCity, SCTY, -63%, $681,853,056

Tesla, TSLA, -40%, $2,778,478,267

Source: S&P Global Market Intelligence, USA TODAY

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