To add or not to add, that is the question.

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As investors anticipate Tesla’s December 21 addition to the S&P 500, investors who benchmark their performance against the index have a tough decision to make. As JP Morgan analysts wrote this week: “We have recently fielded a number of calls from long-only investors who are faced with or shortly will be faced with the decision of whether or not to buy Tesla shares.”

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The bank’s answer?

“We recommend investors not weight Tesla shares in their portfolio in equal proportion to the S&P because Tesla shares are in our view and by virtually every conventional metric not only overvalued, but dramatically so.” 

Tesla shares closed at $627 on Thursday. As the analysts led by Ryan Brinkman wrote, investors should “consider that in the two years since December 8, 2018 during which TSLA shares have risen +808% and during which analysts have on average increased their 12 month price targets by +451%, analysts have simultaneously lowered their estimates for Tesla EPS for 2020, 2021, 2022, 2023, and 2024.” 

The contrarian JP Morgan take comes as other Wall Street banks have grown more bullish Tesla’s outlook. Last week Goldman Sachs upgraded the stock from neutral to buy, ratcheting up their 12-month price target from $455 to $780. As Fortune wrote, “Goldman’s analysts cited a few reasons for their change of heart. They believe EV adoption is accelerating due to battery prices falling faster than they had expected, combined with an increase in regulatory proposals to limit or ban the sale of internal combustion engines over the next few decades. As a result, the analysts ‘now expect EVs to comprise 18% of sales globally in 2030 and 29% in 2035 (with 50% adoption in 2035 in both the US and in Western Europe).’”

Wedbush analyst Dan Ives also upgraded the stock, sticking a “bull case” target of a $800-$1,000 on TSLA shares (his 12-month target, meanwhile, is below Goldman’s at $560). 

Indeed, betting against Tesla has been a trying proposition in 2020. As Fortune‘s Aaron Pressman wrote recently, “Short sellers, including Enron-conquerer Jim Chanos, have lost so much money betting that Tesla’s stock price would collapse (it’s up almost eightfold this year) that Institutional Investor dubbed it the ‘widow-maker trade of 2020.’ By this month, the cumulative loss of shorters on Tesla exceeded $35 billion.”

And while a Biden Administration is anticipated to be a positive for Tesla and its ilk, the primary concern about the stock remains the fact that the company is overly reliant on a declining business of selling emissions credits, and that it simply cannot sell enough cars to justify its current market cap. As JP Morgan concluded: “We do not believe Tesla will grow to approximate 2x the combined size of Toyota & VW at the same margin (or 1⁄2 the combined size at 4x the margin, or any of the other combinations of volume and margin that could be reverse engineered” to justify the current valuation.

Which is why the bank has an “underweight” rating on the stock, with a price target of—yes you are reading this right—$90.

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This story was originally featured on Fortune.com