Focused on building reliable datasets, financial models, and research tools for value-minded investors. Committed to turning complex data into practical guidance for value-investing and long-term wealth.
Dr. Charlie Tian is the founder and CEO of GuruFocus.com, a leading global investment research platform established in 2004. With a Ph.D. in physics, Dr. Tian transitioned from science to finance, applying a data-driven, disciplined approach to value investing.
The Relative Strength Index (RSI) is a momentum oscillator that measures the speed and change of price movements. The RSI is most typically used on a 14-day period, measured on a scale from 0 to 100. Traditionally, an asset is considered overbought or overvalued when the RSI is above 70 and oversold or undervalued when it is below 30. A shorter period RSI is more reactive to recent price changes, so it can show early signs of reversals. 9-Day RSI is sometimes used together with 14-Day RSI in a two period divergence strategy.
The industry rank for Lee Chang Yung Technology's 9-Day RSI or its related term are showing as below:
TPE:4989's 9-Day RSI is ranked better than 74% of 2685
companies
in the Metals & Mining industry
Industry Median: 42.7
vs TPE:4989: 35.90
Lee Chang Yung Technology (TPE:4989) 9-Day RSI Explanation
The Relative Strength Index (RSI), developed by J. Welles Wilder in his book “New Concepts in Technical Trading Systems.”, is a momentum oscillator that measures the speed and change of price movements. The RSI is most typically used on a 14-day period, measured on a scale from 0 to 100.
Traditionally, an asset is considered overbought or overvalued when the RSI is above 70 and oversold or undervalued when it is below 30. A RSI surpasses the 30 level indicates a bullish sign, when it slides below 70 level, it’s a bearish sign. This level can be adjusted depending on the security’s pattern and the market’s underlying trend. In an uptrend or bullish market, the RSI might range within a higher interval, investors could set the support level higher. If a downtrend or bearish market occurs, investors may need to lower the resistance level.
RSI can also be used in trading techniques to indicate the trading signal, such as Divergences and Swing Rejections. A shorter period RSI is more reactive to recent price changes, so it can show early signs of reversals. 9-Day RSI is sometimes used together with 14-Day RSI in a two period divergence strategy.
Lee Chang Yung Technology 9-Day RSI Related Terms
TPE:4989 vs SCCO, FCX: 9-Day RSI Comparison
For the Copper subindustry, Lee Chang Yung Technology's 9-Day RSI, along with its competitors' market caps and 9-Day RSI data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Lee Chang Yung Technology 9-Day RSI vs Metals & Mining Industry
For the Metals & Mining industry and Basic Materials sector, Lee Chang Yung Technology's 9-Day RSI distribution charts can be found below:
* The bar in red indicates where Lee Chang Yung Technology's 9-Day RSI falls into.
Lee Chang Yung Technology (TPE:4989) 9-Day RSI Calculation
The formula for calculating RSI is:
RSI
=
100
–
[ 100
/
( 1 + Average Gain
/
Average Loss )]
* Note that the formula uses a positive value for the average loss.
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Lee Chang Yung Technology (TPE:4989) has a 9-Day RSI of 35.90 as of Jul. 16, 2026. According to the industry distribution chart, Lee Chang Yung Technology ranks #698 out of 2685 companies in the Metals & Mining industry, placing it in the top 26%.
Is Lee Chang Yung Technology's 9-Day RSI too high?
Lee Chang Yung Technology's current 9-Day RSI is 35.90. The Metals & Mining industry median 9-Day RSI is 42.70. Lee Chang Yung Technology's value of 35.90 is 15.9% below this industry median. Based on the distribution chart, Lee Chang Yung Technology ranks #698 out of 2685 companies in the Metals & Mining industry, which is above the industry midpoint. Overall, Lee Chang Yung Technology has a GF Score™ of 50/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Lee Chang Yung Technology's 9-Day RSI compare to SCCO and FCX?
According to the Metals & Mining industry distribution chart, Lee Chang Yung Technology ranks #698 out of 2685 companies for 9-Day RSI. This puts Lee Chang Yung Technology in the upper half of its industry. The industry median 9-Day RSI is 42.70. Lee Chang Yung Technology's value of 35.90 is 15.9% below this benchmark. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good 9-Day RSI for a Metals & Mining company?
The median 9-Day RSI among Metals & Mining companies is 42.70, based on 2,685 companies in the industry. Companies in the top quartile (top 25%) have a 9-Day RSI significantly above this median, while those in the bottom quartile fall well below. However, 9-Day RSI should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Lee Chang Yung Technology's current 9-Day RSI of 35.90 is 15.9% below the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high 9-Day RSI mean?
A high 9-Day RSI can signal that a stock is expensive relative to its fundamentals. For the Metals & Mining industry, the median 9-Day RSI is 42.70 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Lee Chang Yung Technology's current 9-Day RSI is 35.90. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Lee Chang Yung Technology stock overvalued right now?
Based on GuruFocus' analysis, Lee Chang Yung Technology (TPE:4989) is currently considered Significantly Overvalued. The stock's GF Value™ is NT$16.64, compared to a current price of NT$80.00 — trading 380.8% above its estimated fair value. The current 9-Day RSI is 35.90 and 15.9% below the Metals & Mining industry median of 42.70. Lee Chang Yung Technology's overall GF Score™ is 50/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is 9-Day RSI calculated?
9-Day RSI is calculated from a company's financial statements. For Lee Chang Yung Technology (TPE:4989), the current 9-Day RSI is 35.90 as of Jul. 16, 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Lee Chang Yung Technology (TPE:4989) Overvalued in 2026?
Based on GuruFocus' analysis, Lee Chang Yung Technology stock appears to be overvalued.
The current stock price of NT$80.00 is trading 380.8% above its estimated GF Value™ of NT$16.64.
GuruFocus considers Lee Chang Yung Technology to be Significantly Overvalued.
Key valuation signals for TPE:4989:
9-Day RSI: 35.90
GF Value™: NT$16.64 vs. price of NT$80.00 (380.8% above fair value)
Industry Position: 15.9% below the Metals & Mining median (#698 of 2685)
No single metric tells the full story. See the TPE:4989 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Lee Chang Yung Technology Corp produces, manufactures, and sells electrolytic copper foil, an upstream material for printed circuit boards. The Group currently sells a single product, copper foil.
50GF Score
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9-Day RSI is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.
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