Tesla certainly has some work to do. And that’s because the registration for Tesla Inc. vehicles in California, certainly their largest market, fell 24% in April from one year ago. This is according to data from HIS Markit.

Of course, Tesla says that this information is misleading because the deliveries vary so much from month-to-month. Sales of electric vehicles throughout the United States remain at less than 1% of total vehicle sales. In December of 2016 and January of 2017, many were getting excited as Tesla’s Chief Executive Elon Musk started working on a strategy to diversify production of other items such as storage batteries, electric commercial trucks, rooftop solar panels and more. However, Tesla shares started to fall in June with concerns that the company’s current models were having weak sales.

HIS analyst Stephanie Brinkley did caution that just looking at a single month doesn’t show the full picture. As she said, “If Tesla had an issue with its production for the month, that could explain.” However she did say that, “They haven’t changed much on the exterior or much on the package. I can certainly understand where Model S sales may be softening a little bit because it’s an older product. That could be contributing to the issue.”

Learn more about Tesla and the ups and downs they are having here.