Let’s talk a little bit today about one of the major risks that could impact your retirement, and there’s nothing you can do about it.

Well, besides a sale down at the glitter store. SHUT UP I LIKE GLITTER, OKAY?

This big risk is what happens if the economy stays stuck in a rut for years and your investments stay stagnant for the better part of a decade? Or even longer?

Some might laugh at the sheer notion of a lost decade or some other such nonsense, usually folks who have little investing experience outside of this current bull market. But these things happen. And more often than you’d think, too.

It took the S&P 500 a full 12 years to surpass its all-time high (set back in 2000) in a meaningful way. U.S. stock markets also famously languished for more than a decade from 1968 to 1982. Japan has seen the Nikkei fall some 40% since all-time highs set in 1989. And so on. Like I said, these lost decades happen. All the time.

So what’s an investor to do today, as worldwide markets bump up against all-time highs again? How should you plan for another lost decade, which does tend to happen after long bull markets?

You don’t.

Focus on what you can control

You can’t control what the market is going to do over the short-term or even the long-term. All you can control is how much money you put away, what you spend, your asset allocation, and your proximity to the glitter store. A glitter sale? I’ll see you guys in three months!

Dude, enough with the glitter jokes.

Nah. I figure I’ve got another three decades until those stop being funny.

Your savings rate is the big one, of course. A high savings rate can erase a lot of other sins. Which is a good thing, because index funds might not be the best investing choice going forward. How well is an index fund going to perform if underlying stocks don’t go up? I’m no mathematician, but I’m going to guess the answer is not great.

But if you keep shoveling money into the market, eventually stocks will go up again. There’s a reason why every financial commentator this side of Nairobi advocates dollar cost averaging — because it works. And I’m happy with my dividend portfolio, churning out ever-increasing income each year, no matter what the market does. Unless the market really goes to shit, of course.

You can also diversify your portfolio outside of the stock market. Bonds are the easy choice, and they come with the bonus of holding up pretty well if stocks don’t. You could invest in real estate (either via physical property or REITs, although the latter is at risk of rising or falling with the overall market) or private mortgages. I know when the market was crashing hard back in the fall my private mortgage portfolio didn’t see a cent of decline.

And so on. There are a million asset classes out there. Take your pick. I suggest glitter Beanie Babies. I hear those things are making a comeback.

Keep on chugging

It’s challenging to consistently put cash to work during times of market weakness. It’s one of the reasons why I’m not a big fan of doing up my net worth on a monthly basis. It’s too easy to get discouraged during a tough period, although it’s pretty fun to do when markets go up a lot.

If you just focus on saving enough and investing those savings in an index or what you view as great businesses, then you’re bound to get ahead in the long-term, even if there’s some short-term pain in the meantime.

Tell everyone, yo!