The S&P/ASX 200 Index (ASX: XJO) is a magnificent share market. As my Fool colleague Brooke Cooper discussed this morning, there are many things to love about our flagship market index. We have a plethora of impressive, world-class businesses. We have strong transparency and insider trading laws. And the ASX 200 has, over time, delivered strong, inflation-smashing returns that would make any other asset class blush.
But nothing is perfect in its world. And the ASX 200 is no different. So what exactly is the ASX 200's Achilles heel?
Well, see if you can guess after the top 10 ASX 200 companies by market capitalisation are listed here. The weightings are according to iShares in the iShares Core S&P/ASX 200 ETF (ASX: IOZ).
| ASX 200 Share | ASX 200 Weighting |
| Commonwealth Bank of Australia (ASX: CBA) | 7.89% |
| BHP Group Ltd (ASX: BHP) | 6.94% |
| CSL Ltd (ASX: CSL) | 6.06% |
| Westpac Banking Corp (ASX: WBC) | 4.72% |
| National Australia Bank Ltd (ASX: NAB) | 4.49% |
| Australia and New Zeland Banking Group Ltd (ASX: ANZ) | 4.21% |
| Wesfarmers Ltd (ASX: WES) | 3.01% |
| Macquarie Group Ltd (ASX: MQG) | 2.66% |
| Woolworths Group Ltd (ASX: WOW) | 2.58% |
| Rio Tinto Limited (ASX: RIO) | 2.12% |
So these 10 ASX shares make up around 44.7% of the entire index. See any patterns? Let me help out. CBA, Westpac, NAB, and ANZ, as well as Macquarie, are all ASX banks. These banks together make up approximately 24% of the ASX 200. Throw in the large miners in BHP and Rio Tinto and we get to 33%.
Sure, we have a healthcare company in CSL, as well as retail giants in Woolworths and Wesfarmers. But it's still not what you would call 'balanced'.
Image source: Getty Images
The ASX 200's Achilles heel
You might notice one glaring omission in this list: ASX tech companies. Sure we have many quality tech companies on the ASX. There's Afterpay Ltd (ASX: APT), Altium Limited (ASX: ALU), and Xero Limited (ASX: XRO). But none of these companies, even together, have a massive, or even significant, presence in the ASX 200. Even Afterpay is only worth 1.33% of the index.
Yet tech is going to be a big part of the future of the ASX 200 if the growth of this sector over just the past year is any kind of indication. This could be called the ASX 200's Achilles heel.
So how do we combat this Achilles heel? One way could be by turning to overseas sharemarkets. Take the United States. The US has two of the most popular indexes int the world in the S&P 500 Index (INDEXSP: .INX) and the NASDAQ-100 (INDEXNASDAQ: NDX). Both of these indexes are dominated by tech companies like Apple Inc (NASDAQ: AAPL), Microsoft Corp (NASDAQ: MSFT), Amazon.com Inc (NASDAQ: AMZN), Tesla Inc (NASDAQ: TSLA), and Facebook Inc (NASDAQ: FB). Both can be accessed via exchange-traded funds (ETFs) on the ASX such as the iShares S&P 500 ETF (ASX: IVV).
Another option one could consider is the BetaShares Asian Technology Tigers ETF (ASX: ASIA). This ETF holds a portfolio of Asian tech shares like Alibaba Group Holding Ltd, Tencent Holdings, and Taiwan Semiconductor Manufacturing Company.
Adding a tech-based ETF to your ASX share portfolio could well plug the ASX 200's Achilles heel. We can all love our index. But recognising its flaws could help strengthen your ASX portfolio. Something to keep in mind!
