Tesla has just finished its best day of the year

Tesla has its best day of the year Tuesday, closing more than 8%. The rebound added more than $ 2 billion to its market capitalization, which now stands at $ 34.2 billion.

Despite this boost, the Tesla stock has fallen by almost 42% in 2019, making it the worst performance of the year for the Nasdaq 100. In comparison, Mylan N.V., the worst performer of the S & P 500, has sold about 35% over the year.

Tesla shares fell as the company entered cost-cutting mode and analysts questioned the demand for its vehicles and its future in China. Last week, Tesla shares fell below the valuation of the private company of CEO Elon Musk, SpaceX. Investors familiar with SpaceX's latest round of funding told CNBC its value was $ 33.3 billion.

Tesla may have fallen so far that it's now a good buy, according to Carter Worth, a technical analyst at Cornerstone Macro. Worth said on Tuesday, in CNBC's "Fast Money" show, that Tesla had "underperformed by an amount that makes it so bad that it's good".

Tesla jumped early last month after revealing its intention to raise $ 2 billion. In a deposit, Musk announced plans to buy about $ 10 million of the title.

But soon after, Musk announced to its employees, in an email obtained by CNBC, that the funds would allow it to go through 10 months if it could not reduce its expenses. Musk wrote that the "drastic" cost-cutting measures would be so detailed that he would "personally review and sign every tenth page" of outgoing payments.

Tesla has made significant progress in achieving its production targets for Model 3 for the second quarter, according to another Musk e-mail leaked last month. CNBC previously announced that its car plant in Fremont, Calif., Would increase production of its crossover SUV Model Y, which is a growing segment.

However, the financial health of the company still faces several challenges, including the impact of tariffs in China. Loup Ventures co-founder Gene Munster said last month that shipments to China would drop from 70,000 to 40,000 vehicles, with some Chinese consumers likely to avoid the brand.

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Look: Tesla being at its lowest in three years, a reputed technician states that the stock is so bad that it is worth buying now.