Upstart's stock has fallen more than 87% this year.The artificial intelligence-assisted lending platform Upstart(UPST-1.94%)has gone from trading at all-time highs in 2021, when shares hit nearly $400, to all-time lows, with shares trading below $18.It has been a topsy-turvy ride for the fintech company, which believes its proprietary algorithms can underwrite loans better than more traditional methods such asFair Isaac'sFICO scoring. High inflation, followed by rapidly rising interest rates, has disrupted a key part of Upstart's business model, making formerly enthusiastic investors reverse course.But with the company now trading much lower, are shares due for a big rebound next year? Can the stock rise back up to $45 per share, a level it traded at for nearly all of 2021?IMAGE SOURC