It's been a quiet day for markets across the world,

reflecting a general lack of a conviction either positive or negative that's been around for some weeks.

But you did have one rather intriguing development here in the States, just there was further pressure on Apple,

which means, as you can see from this chart, that Apple's title as the world's largest company is once again under threat, this time from Google.

You can see that Google briefly overtook it earlier this year, it appears likely to do so again.

Now, this is part of a longer term pattern.

Apple is under pressure, it is now as low as it has been in two years.

If we now take a look at this next chart, you can see that in the time since it was last at this level,

Google has managed to continue to log steady, regular progress.

You haven't seen that from Apple, obviously there is a great concern about revenues from the iPhone, they appear to be set to decline.

It should of course, always have been in the price that at some point, iPhone revenues will inevitably peak and start to slow down,

but it still seems somehow to have taken people by surprise.

Now, I'm not gonna make any predictions about the short term,

it's quite possible that Google, which is obviously a very great company, will be a great investment for a while,

but for the longer term I am prepared to suggest that it would not be a good idea to invest in Google.

Now, we can illustrate that for you if we take a look now at the performance.

This is the market cap of the six companies to have been the largest in the S&P since 1990, in the last quarter of a century,

we're excluding Cisco Systems, which was the #1 for a few days back in the madness of the tech bubble in 2000.

And you can see that there is one very clear pattern that emerges from all of those is that companies don't get superseded as the largest by seeing somebody overtake them.

They tend to get superseded as the largest by falling themselves, you can see that befalling GE, Microsoft, and now it's happened to Apple.

Now, in many ways, that would make sense.

If you get to be the largest company, it implies that you are very fully valued, or that you have a business model that is working about as well as it possibly could,

and that will naturally tends to attract more competition or more attention from the Antitrust Authorities.

If we take a look at this final chart,

what you can see here is how the four companies that were the largest at some point during the 1990s have faired during this century since the beginning of 2000.

This is all relative to the S&P.

And you can see that only Exxon among these is even managed to be ahead of the market,

and in Exxon's case that's very much driven by the oil price and it's underperformed very drastically since the top of the oil market in 2008.

In general, if we've gone back to some of the previous largest companies,

like DuPont, General Motors, or Walmart or AT&T, all great companies at one point, all pegged back for good reason.

The point would perhaps become even clearer, it's just not a great idea once a company is already the biggest to invest in it.

Congratulations Google. For the longer term it's probably not a great investment.