Think Nvidia Stock Is Expensive? These 3 Members of the S&P 500 Trade at Even Higher Valuations.

Is Nvidia (NASDAQ: NVDA) stock overvalued? This question, while simple on the surface, is extraordinarily hard to answer.

Many investors use a valuation metric called a price-to-earnings (P/E) ratio. This popular metric is useful because it measures the stock price against a company’s profits. And in Nvidia’s case, its P/E ratio of 57 certainly looks expensive, considering it’s roughly double the P/E ratio for the S&P 500.

Then again, context is important. Nvidia stock might look expensive now. But it actually trades at a steep discount to its average P/E ratio valuation over the last five years, as the chart below shows.

NVDA PE Ratio data by YCharts.

Many say to avoid stocks with a high P/E ratio. But Nvidia’s high P/E over the last five years didn’t prevent the stock from rising over 2,700%.

Nvidia stock is now cheaper than its five-year average valuation. Moreover, it’s not even the most expensive constituent of the S&P 500. In fact, Axon Enterprise (NASDAQ: AXON) and CrowdStrike (NASDAQ: CRWD) trade at higher P/E ratios, as of this writing. And even Costco Wholesale (NASDAQ: COST) has been more expensive than Nvidia at times in recent weeks.

Axon provides hardware and software to law enforcement agencies. CrowdStrike is a cybersecurity specialist. And Costco is a grocery and home-goods retail chain known for its membership-business model and low prices. As the chart below shows, none of these companies are necessarily cheap when looking at the P/E ratio.

NVDA PE Ratio data by YCharts.

Should investors sell stocks when their valuations are high? Should they only buy stocks that trade with below-average valuations?

If the path to long-term wealth were this simple, all investors would be rich. The entire investing process could be automated to sell when a P/E ratio was high and buy when a P/E ratio was low. But it’s not that simple. As I said at the start, it’s extraordinarily hard to say when a stock is actually overvalued.

Famous investor Bill Miller succinctly explains why valuing a stock is difficult. Miller has said, “100% of the information you have about a company represents the past, and 100% of the value depends on the future.”

Imagine for a moment a company valued at $10 billion and that has only made $1 million in profit. That stock would look extremely overvalued using the information we have from the past. But Miller reminds us that value has to do with the future. If this same $10 billion company earns $100 billion in profit over the next five years or so, then the stock is a screaming value stock.

In my opinion, whether Nvidia is overvalued or undervalued today largely depends on how sustainable its profit margins are. As the chart below shows, its margin has soared as artificial intelligence has fueled demand for its hardware products.