One of the fastest cars on the planet, sales of the Tesla Model S have been slowing in recent months, being surpassed by its showroom sibling, the Model X SUV and left in the dust by the class-leading Model 3. Still, it accounted for 7,225 units delivered over the last six months, which is not too shabby. March was its strongest month with 2,175 units delivered. However, a year ago at this time Tesla had sold 10,820 Model S sedans, with 3,375 of them in March of 2018.