But his close relationship with Donald Trump appears to be hurting Tesla's car sales, which were down 17% last year in Australia, and they dropped by more than 30% last month.

In Europe, it was even worse, especially in France and Germany, where sales last month plummeted by more than 60%.

For more on what's behind this, I spoke to Giles Parkinson, founder and editor of The Driven.

Hello there, Giles.

Tesla shares have taken quite a hit, as you can see.

How much of this can be traced to Elon Musk himself and his personal brand?

It's always hard to quantify exactly the effect that Elon Musk is having, but the anecdotal evidence suggests it's very strong.

You've mentioned Australia.

Sales in January were one quarter of what they were two years ago.

Now, the overall market has not been strong, but Tesla has accounted for more than half of the Australian EV market in the last few years.

So when they fall, it affects the rest of the market.

We've seen that in Europe also, where the market is probably stronger than it is in Australia.

In Norway, for instance, which is already at 96% electric vehicle share of the market, and has actually been quite strong in the last month, Tesla has slumped quite sharply.

It used to be the top selling EV in that market.

Now it's number six or number seven.

And we've seen that in France, in Spain, in UK, Germany, Netherlands, Portugal, the share of the number of Tesla sales has fallen significantly.

And that really has been attributed a lot to the impact of Musk on his brand.

And over in the US, Tesla sales have gone backwards as well in the blue state of California, where the company's headquarters used to be.

So what can you tell us about that?

Well, I think that's more of a pushback against Mr. Musk's politics.

As you say, California is a blue state.

It's the birthplace of Tesla.

It's where the headquarters used to be.

It's where the first manufacturing plant used to be.

It's where he can see so many Teslas on the road.

And we're hearing that people are walking into other car makers and saying, look, I want to buy an electric car, but I don't want to buy Tesla anymore.

And we're also hearing that people who own Teslas are feeling uncomfortable about that and looking to see if they can either sell and shift to another brand.

It's an extraordinary situation because the Tesla products are really quite admired because of their quality.

But some people are just finding it really to either buy or retain those cars.

So, Giles, are these weaker sales results a cautionary tale on what happens when a company boss gets too involved in politics?

Well, I don't think we've ever seen anything quite as extraordinary as Mr. Musk's involvement in politics.

I mean, he seemed to have taken such a dominant role in the US administration that no one could really have predicted and no one has ever seen before.

You know, you think about other car makers.

I mean, do we really worry?

Do we know what the head of Toyota or even the Chinese government thinks about its politics?

But there's been something about Mr. Musk's interventions, both in his political actions, but also what he said on Twitter, which is sort of causing quite a reaction amongst consumers.

And are there any other factors which could be involved, for instance, more competition from Chinese EVs, which tend to be cheaper?

Well, we're certainly seeing that, and particularly in Australia.

Tesla used to dominate this market, and now we're seeing those Chinese car makers coming in with lower priced and really quite good quality vehicles.

There's also issues around inventory.

Some people might have been waiting for the upgraded Model Y, which has been the best selling EV in Australia for a while now and is coming up with an upgrade in six months.

So maybe some people are delaying their decision on that basis.

So it would be wrong to say that Mr. Musk is the only impact on the stock.

There are other factors, but I don't think it would be right to say that he's having no impact.

So overall, these falling sales, is this just a blip or the start of a more concerning trend for Elon Musk?

Well, we'll have to wait and see.

Certainly the signs in Europe and North America are not looking good.

In Australia, I guess the test here and in other markets will be the success of the new Model Y upgrade.

But in Australia, it has a big impact because we now have a target for electric vehicles.

We're trying to increase the rollout of those.

Tesla has accounted for half the market in just the last year.

If they continue to fall, then we're going to see major issues and a much slower uptake of EVs overall, and that's going to have an impact on the whole market, really.

Giles, thanks a lot for your insights.

Really appreciate it.

Thank you.