• Prices for used Teslas are dropping faster than the rest of the used-car market, Reuters reported. 
• Secondhand Tesla prices dropped by some $11,500 between July and November. 
• Tesla investors are worried about waning demand for the company's electric cars. 

If you've been holding out to buy a Tesla until prices came down, your wait may be over. 

Prices of secondhand Teslas have dropped faster than used cars from other brands, Reuters reported Tuesday, citing data from Edmunds. It may be great news for buyers who have delayed an electric-car purchase because they're too expensive. 

In July, the average used Model 3, S, X, or Y would have cost you $67,297. But by November, prices slid 17% to $55,754. Used-car prices on the whole are also coming down after years of short supply, but not as sharply, dropping 4% over the same period, according to Edmunds data. 

Teslas are also sitting on used-car lots for longer than other brands' vehicles: 50 days as opposed to 38 days, Edmunds said. Declining gas prices, competition from other brands, and high interest rates are all contributing to the dropping prices, Reuters reported. 

Used Teslas losing value could impact demand for the brand's new cars, Karl Brauer, executive editor at the car search engine iSeeCars.com told Reuters. People who bought new Teslas over the last couple of years could often flip them for a profit, Brauer said, but that's not possible anymore.

Tesla shares have been in a downward spiral amid fears that demand for its cars is waning after years of ferocious growth. The company discounted some of its cars by $3,750 in December, then doubled the deal just a week later. And the automaker is reportedly slowing down production in China, the world's biggest car market. 

As of Wednesday morning, Tesla shares were down more than 70% this year.