Invesco RAFI Strategic US ETF (IUS)

IUS holds a basket of large US companies, but it doesn’t use the same method as regular stock-market indexes. Most index funds weight holdings by market cap — Apple gets a bigger slice than Microsoft just because Apple costs more. IUS uses a different rule: it picks and weights companies based on fundamental financial metrics like sales, cash flow, and book value. The idea is simple: let the size of a business guide how much you own of it, not how much investors are willing to pay.

What RAFI indexing means

RAFI stands for Fundamental Index, a methodology created by Research Affiliates. The approach starts with US large-cap companies but selects them and sizes them differently than the S&P 500 does. Instead of using stock price to determine weight, it looks at the past four years of a company’s sales, cash flow, book value, and dividends. This way, a business that earns the same money as a pricier competitor gets equal or greater weight in the fund.

The reasoning is: market cap reflects what investors think a company is worth today; fundamentals reflect what it actually earned. When the market bids up mega-cap growth stocks and leaves unglamorous value stocks cheap, a fundamental-index approach naturally tilts the fund toward value — not because a manager made a deliberate call, but because fundamentals and price happen to diverge. This tilt is intentional and often appeals to investors who believe value is undervalued when growth stocks soar.

How IUS differs from the S&P 500

The biggest difference shows up in the portfolio’s heaviest holdings. A traditional cap-weighted index puts roughly a third of its weight in the ten largest companies — in recent years, mostly mega-cap tech. IUS, weighted by fundamentals, spreads its weight more evenly. A financial services firm that is large and profitable but whose stock price has not soared gets more room in IUS than it would in the S&P 500. This reduces concentration risk: instead of betting heavily on whether Apple, Microsoft, and Nvidia keep outpacing the market, IUS spreads exposure more widely and picks up overlooked profitable businesses.

Over periods when value has outperformed growth, this tilt has boosted IUS’s returns. Over periods when growth has dominated, IUS has lagged. This is not a flaw in the methodology — it is the trade-off built in. The fund is not trying to beat the market; it is offering a different, rule-based exposure to large-cap America.

Costs and how it trades

IUS carries an expense ratio that is modest — roughly in line with other passive ETFs — and trades with solid liquidity on the Nasdaq. Invesco rebalances the fund periodically to keep weights aligned with the latest fundamental data. This creates some tax drag in taxable accounts but also brings recent earnings data into the mix rather than freezing weights for a full year.

The cyclical case for fundamentals

The appeal of fundamental weighting waxes and wanes with market cycles. When the market gets intoxicated with growth stories, cap-weighted indexes pull forward and leave value behind — and IUS underperforms. When the cycle turns, when profit growth matters more than narrative, when expensive stocks correct, the fundamental tilt often adds value. Cyclically, this is a fund that works best for investors who believe the current cycle favors value or who want to hedge against continued growth outperformance by holding a different, fundamental-first lens on the same companies.

For a long-term holder, IUS is a reasonable substitute for the S&P 500 if the goal is to own large US companies but with less concentration in the largest and priciest. It is not a market-beating strategy — just a different way to own America’s largest public firms.