Just about all of us need to be saving and investing for our retirements, because Social Security, while vital, won't support us well on its own. The recent average monthly Social Security retirement benefit was $1,665, or about $20,000 annually.

Sadly, many, if not most, of us are behind in our saving and investing. According to the 2021 Retirement Confidence Survey, only 72% of workers surveyed reported having saved anything for retirement, and many of those had saved far less than they should have to reach their retirement goals. It's not too late to do better, though.

Shot of a young couple dancing together in their kitchen.

Image source: Getty Images.

Here's an easy investing strategy that can help you build wealth for your future -- plus an exchange-traded fund (ETF) that can supercharge the strategy.

An easy, basic strategy

It's a shame that many people put off or avoid investing because it seems complicated and intimidating. It doesn't have to be. You don't have to read a dozen books on investing or spend hours per week studying stocks, deciding which to buy or sell.

Instead, you could just park most or all of your long-term money (dollars you won't need for at least five, if not 10, years) in one or more low-cost, broad-market index funds. Each index fund aims to deliver roughly the same return as the index it tracks, less fees. Here are three solid ones to consider:

  • SPDR S&P 500 ETF (SPY -0.21%)
  • Vanguard Total Stock Market ETF (VTI -0.21%)
  • Vanguard Total World Stock ETF (VT -0.15%)

Respectively, these investments will instantly invest your money in roughly 80% of the U.S. stock market, the entire U.S. stock market, or just about all of the world's stock market. Sock money away into one or more of them (or other good index funds) regularly, and over many years, your wealth should grow.

Over your particular investing time frame, the stock market might average annual returns of, say, 7%, or maybe 12%. There's no way to know. Over very long periods, it has averaged close to 10% annually. The table below is a bit conservative, reflecting 8% annual growth, and it shows how much you might amass over time simply with index funds:

Growing at 8% for...

$10,000 Invested Annually

$15,000 Invested Annually

$20,000 Invested Annually

5 years

$63,359

$95,039

$126,718

10 years

$156,455

$234,683

$312,910

15 years

$293,243

$439,865

$586,486

20 years

$494,229

$741,344

$988,458

25 years

$789,544

$1,184,316

$1,579,088

30 years

$1,223,459

$1,835,189

$2,446,918

Data source: Calculations by author.

Supercharge your investing strategy

That's pretty impressive growth. You might want to aim for faster growth, though. If so, consider parking some of your money in the Invesco QQQ Trust (QQQ -0.57%). It's an ETF that's made up of the 100 largest nonfinancial companies listed on the Nasdaq stock market (measured by market capitalization).

It's not guaranteed to outpace the overall U.S. stock market, but its track record is pretty good:

Average Annual Return Over...

Invesco QQQ Trust

5 years

20.6%

10 years

18.5%

15 years

15%

Source: Morningstar.com, as of Apr. 22, 2022. 

If you look at its recent top 10 holdings, you'll get an idea of how it has been able to deliver such returns:

Company

Allocation

Apple

12.67%

Microsoft

9.97%

Amazon.com

7.28%

Tesla

4.69%

Alphabet (Class C shares)

3.76%

Alphabet (Class A shares)

3.58%

Nvidia

3.51%

Meta Platforms 

3.22%

Costco

2.06%

Broadcom

1.89%

Source: Invesco.com. 

The fund has around 90 other holdings, too, including lots of well-regarded businesses, such as:

  • Intel 
  • Amgen
  • Netflix 
  • PayPal
  • Adobe 
  • Starbucks 
  • Airbnb
  • Intuitive Surgical
  • Zoom Video Communications 
  • Lululemon Athletica 

So give these investing strategies some thought -- especially if you need to do better than you've been doing. The first one alone, a simple index fund or two, can be enough for you -- and if you want to aim higher, consider putting some money in the QQQ ETF. Don't leave your future financial security up to chance -- and don't assume Social Security will be enough.