What happened

Shares of Chinese solar-module maker JinkoSolar Holding (JKS -1.29%) are taking a tumble this afternoon, falling 9.9% as of 2:40 p.m. EDT after analysts at Swiss megabank UBS downgraded the shares from neutral to sell.

Earnings don't appear to be the problem here. Indeed, Jinko isn't even scheduled to report earnings again until mid-November. Instead, the problem is a simple matter of valuation... and profits.

Chinese flag superimposed on a stock market chart

Image source: Getty Images.

So what

Solar stock JinkoSolar has been a big winner for investors this year, more than quadrupling in stock price over the past 52 weeks. The stock has fallen into something of a funk of late, however, sliding 33% in the last five trading days. According to UBS, now might be a good time to exit from Jinko -- and from other renewable energy stocks, as well -- before they have a chance to fall any further.

Why? On the one hand, opines the analyst today in a note covered by TheFly.com, "a Blue Wave election would result in less-than-priced-in policy support over the next year" -- i.e., the stock could move higher if green-energy friendly Democrats take the White House, the House, and the Senate, too. On the other hand, though, the analyst notes that any election's results are uncertain until they happen, and the risk/reward ratio on Jinko stock still looks skewed heavily to the downside.

Now what

Accordingly, UBS feels that investors should be "cautious" about investing in Jinko today, even after the stock's recent steep slide. When I look at the company's numbers as reported by S&P Global Market Intelligence and see seven straight years of reported GAAP profits -- not one of which was backed up by actual positive free cash flow, however -- I can't help but agree.

There's something fishy about these numbers, and caution should be the order of the day.