Tesla Inc.’s sales plummeted 59% last month in Germany, adding to indications that Chief Executive Officer’s Elon Musk political activities are hurting the carmaker’s business in major electric vehicle markets.

Sales of Tesla cars have nosedived across some of the EV manufacturer’s most valuable European markets—and experts are blaming Elon Musk. Sales in Germany, where Tesla has a factory, dropped a staggering 59 percent in January compared to the same month last year,

The U.S. electric car company’s sales are sliding across Europe, amid what many see as interference in local affairs by Tesla’s chief executive, Elon Musk.