Are you kidding me?

Apple’s stock could “crash the market”?

Apple is in “meltdown”?

Apple “loses $113 billion”?

When I read things like that, sometimes from serious commentators, I hear an echoing voice from my youth.

It’s the voice of the young John McEnroe, aka “Superbrat,” on the sedate Centre Court at Wimbledon in the early 1980s: “You cannot be serious!”

I’m starting to wonder how many people actually understand the basics of the stock market ... even after all we’ve been through over the past two decades.

A stock cannot “break” or “crash” the market.

Volatility is to stocks what rain is to the west coast of Ireland: a perennial feature. Anyone who is still surprised has either had too much Guinness, or too little.

When a big stock rises, it “gains” a lot of paper value. When it falls, it “loses” a lot of paper value. Within reasonable boundaries, this is normal. Apple AAPL, +3.03% is down about 15% from its peak in April. It is still up, slightly, for the year as a whole.

Read:How a deeper dive by Apple could crush this market

Short-term moves in stocks are only relevant if you are looking to buy and want a bargain — or, where a stock may be overvalued, if you are looking to sell.

I wrote not long ago that sales of the new Apple Watch weren’t looking especially lively. Lots of people took potshots at me over that, but since then all the evidence seems to have backed that up. On the other hand, the Apple Watch, while a useful indicator of Apple’s continuing creativity after the sad loss of Steve Jobs, is not enormously material to the stock at the moment. The business still revolves around iPhones and iPads and Mac computers ... and the emerging business of streaming programs on Apple TV.

So if you’re an Apple investor, should you panic about the latest stock decline?

Of course not.

Should you join all those other people in worrying about Apple’s latest technical charts or Bollinger Bands or 50-day moving average, and so on?

Of course not.

A stock is only a piece of paper that gives you the rights to a share of a company’s future profits. That’s it. Despite all this voodoo and talismanic nonsense we hear on the markets, it’s really that simple. Buying shares in a public company is no different, in principle, than owning a local dry-cleaning store or renting out a condo.

Also see:Apple has lost $105 billion in market value

There are two questions that really matter to you as an investor.

First, how much do you have to pay to buy the business?

Second, once you own it, how much cash profit do you get to put in your back pocket at the end of every year?

And on this measure, Apple’s stock, despite the company’s gigantic market value, still looks pretty reasonable.

Here’s the math.

Apple’s stock currently trades at $114. But even after paying off its liabilities (and Uncle Sam), the company could afford to hand out something like $12 per share in cash, so a share is really only costing you about $102.

What do you get for that money?

Over the past five years, the company has averaged pretax profits of around $7 per year per (current) share. For the past three years, that’s been around $9 to $10 per share. In other words, if you own this dry cleaner, you’re currently getting about a 10% annual return on your money. (Operating cash flow, another useful way of looking at things, is in the same ballpark — it has varied between $9 per share and $11.5 per share over the past three years.)

And analysts so far are predicting things will remain at that level or even rise a bit over the next few years.

(Yes, you have to figure that profit margins will be squeezed in the future. The replacement cycle for iPhones surely cannot remain as crazy as it has in the past. At some point, smartphones must lose some of their gawp factor. On the other hand, there is huge growth to be had in the developing world. And despite the competition, Apple seems to remain the brand of choice. I’ve lost track of the friends who’ve abandoned their iPhones for Android, only to go back to iPhones.)

Apple may not be the exciting go-go stock of yesteryear: Apart from anything else, it is simply too big for that. But it’s hard to argue that it’s wildly overvalued, or that the stock is somehow destined to “collapse.” And if it gets much cheaper, it will start to become increasingly attractive.

Panic? Seriously?