As market rotation persists and sector switching accelerates, investing has become increasingly challenging. Many investors find that industry ETFs they favor often experience sharp volatility after purchase, leading to unsatisfactory outcomes. Industry ETFs concentrate on specific tracks, making their performance susceptible to the sector's own cycles, policy shifts, and capital sentiment. Therefore, conducting some fundamental observations before investing in industry ETFs is essential.

While predicting tomorrow's movements is impossible, we can utilize basic tools to evaluate a prospective sector and assess its current market phase, enabling more rational investment decisions. The following three dimensions examine valuation, trading crowding, and fundamental logic respectively.

The First Dimension: Assessing Valuation Levels to Determine If It's Expensive

Valuation serves as a yardstick for measuring whether an industry is "expensive" or "cheap." We commonly use the price-to-earnings (PE) and price-to-book (PB) ratios for this purpose. An effective and straightforward method involves checking where the industry index's current PE or PB sits within its own historical data's "percentile." This resembles checking where a student's exam score ranks within the class's historical performance.

Low water levels (e.g., historical percentile below 30%): This may suggest the industry is in a "relatively undervalued" zone, with comparatively lower valuation risk. High water levels (e.g., historical percentile above 70%): This may indicate the industry has entered a "relatively overvalued" range, where sentiment is overheated and risks are accumulating.

Quick Tip: The percentile ranges above serve only as empirical references, not absolute buy or sell standards. Different industries have vastly different valuation frameworks, and historical data does not guarantee future performance. In practice, these should be combined with fundamental analysis for comprehensive judgment.

The Second Dimension: Gauging Trading Crowding to Measure Sentiment Heat

If valuation examines price, then trading crowding examines sentiment. It measures an industry's trading activity, commonly observed through the proportion of the industry's trading volume relative to the total market turnover. This is akin to visiting a restaurant—if there's a long queue at the door with bustling noise, entering not only offers a poor experience but may also pose safety risks due to overcrowding. Conversely, if a restaurant is deserted, while quiet, it may also indicate it's temporarily out of favor with diners.

Overheating Signal: When an industry's trading volume proportion continues to climb and breaks through historically high levels, it often implies short-term sentiment has peaked. Chasing at this point can easily leave investors "standing guard" at the top. Freezing Point Signal: When an industry remains neglected for extended periods and its trading volume proportion drops to historical lows, while quiet, it may also suggest pessimism has been fully released—an opportune moment for left-side investors to start paying attention.

However, during extremely strong industry trends or major market rallies, crowding indicators may also "fail." Capital will persistently flow into hot tracks, keeping crowding indicators elevated for extended periods. In such cases, the indicator signals "overheating," yet the market may continue to defy expectations with no end in sight. To address this, implementing strict take-profit and stop-loss discipline can serve as an effective countermeasure.

The Third Dimension: Evaluating Fundamental Logic to Test the Foundation

Valuation and crowding examine price and sentiment respectively, while fundamentals assess the industry's "constitution"—an important basis for evaluating long-term value, though not the sole determining factor. Investors can monitor three straightforward signals: Policy Environment: Does national policy encourage support or impose restrictions? Policy direction significantly impacts industry prosperity. Supply and Demand Dynamics: Is the industry's product in short supply or facing overcapacity? Are product prices rising or falling? Earnings Performance: Are the financial reports of leading companies in the industry showing sustained improvement in revenue and profits?

Yet the fundamental dimension also has its limitations. The stock market acts as an economic "barometer," with prices often leading fundamentals. When bullish news is widely known and earnings reports look stellar, prices may have already fully or excessively reflected these expectations. Chasing at this point risks encountering a pullback where "good news exhausts itself as bad news."

Concluding Thoughts

Valuation, crowding, and fundamentals—none of these three dimensions can provide 100% accurate buy or sell signals. Markets are complex, and every indicator has its applicable boundaries. Expecting a single dimension to offer definitive answers is unrealistic in itself. The essence of investing lies in improving decision-making odds. When all three dimensions resonate—such as valuation at low levels, trading sentiment subdued, and fundamentals showing a turning point for improvement—the confidence in investment decisions may be relatively higher.

Of course, precisely catching the bottom is something only a very few can achieve. For most people, this is not a goal worth pursuing. Therefore, we must emphasize those time-honored yet crucial principles: invest only with idle money, and smooth out costs through phased positioning or systematic investment plans. This not only helps us navigate market volatility but also allows us to maintain a composed mindset throughout the long-term investment journey.

Investing is both a monetization of one's understanding and a contest with one's own emotions. We cannot predict the storms, but we can learn to read the clouds and prepare accordingly, moving forward with composure. Ultimately, what matters more than capturing every fluctuation is safeguarding your investment rhythm and life balance amid market ups and downs.

Risk Disclosure: This article serves solely as investor education content and does not constitute any investment advice. Historical index performance does not predict future returns, and ETFs carry market volatility risks. Diversification and asset allocation can reduce portfolio volatility but cannot eliminate risk or guarantee returns. Before purchasing funds, investors should carefully read the fund contract, prospectus, and product information summaries, selecting products that match their risk tolerance. Regular investing is a simple method guiding investors toward long-term investing and averaging investment costs. However, regular investing cannot avoid the inherent risks of fund investing, does not guarantee investor profits, and is not an equivalent substitute for savings. Funds carry risks; invest with caution.