Price to Earning (P/E) Ratio

The Price-to-Earnings (P/E) ratio is a widely used valuation metric that links a company’s share price to its earnings per share (EPS). It helps you assess whether a stock appears reasonably valued, expensive, or undervalued in relation to its profitability. The ratio is usually calculated using the company’s earnings from the most recent 12-month period.

What is P/E Ratio?

The Price to Earnings Ratio (P/E ratio) compares a company's stock market price with its earnings per share (EPS). It's a key valuation metric indicating if a stock is overpriced or underpriced. The ‘P’ in the numerator represents the current market price, while the ‘E’ in the denominator represents the EPS. This ratio is commonly used in fundamental analysis to identify if a company’s shares are valued more or less than their true intrinsic value.

P/E Ratio Formula: Calculation with Example

You can find a stock’s Price-to-Earnings (P/E) ratio by dividing its current market price by its earnings per share (EPS).
 

P/E ratio = Market price per share ÷ EPS

For instance, if a company’s share trades at Rs. 100 and its EPS is Rs. 5, the P/E ratio works out to 20. This indicates that investors are paying 20 times the company’s earnings for each share. Generally, a higher P/E may point to higher valuation expectations, while a lower P/E can suggest comparatively lower valuation.

Types of price-to-earnings (PE) ratio

There are two types of P/E ratios: trailing and forward. Trailing P/E uses past earnings per share (EPS), while forward P/E is based on projected future EPS, typically estimated by company management or analysts:

1. Trailing P/E ratio

The trailing Price earnings ratio is one of the used metrics by investors, as it is based on a company's past earnings over a specific period. This approach offers a more accurate and objective assessment of the company's financial performance.

2. Forward P/E Ratio

Price to Earnings ratio is calculated by dividing a company's stock price by its projected earnings per share (EPS) based on future earnings guidance. Since this calculation relies on estimated future earnings, it is often referred to as the estimated P/E ratio in stock market. Investors use the forward price-to-earnings ratio to evaluate a company's expected future performance and projected growth rate.

Absolute P/E ratio and Relative P/E ratio

Absolute P/E is the current price-to-earnings ratio. Relative P/E compares it to historical averages or benchmarks to assess valuation in context: 

1. Absolute P/E ratio

The Absolute Price to Earnings ratio, often referred to simply as the P/E ratio, is the straightforward calculation of a company’s current stock price divided by its earnings per share. This ratio gives investors a snapshot of how much they are paying for each rupee of the company's earnings.
 

Formula:

Absolute P/E ratio = Current stock price​/Earnings per Share (EPS)

Uses and interpretation:

• Valuation benchmark: It is used as a benchmark to determine whether a stock is overvalued, undervalued, or fairly valued compared to its earnings.
• Comparative measure: Investors often compare a company’s absolute P/E ratio with the industry average, market average, or historical P/E ratios of the same company.
• Growth and expectations: A higher P/E ratio may indicate that investors expect higher earnings growth in the future, while a lower P/E might suggest the opposite or signal that the stock is undervalued.
   

2. Relative P/E ratio

The Relative P/E ratio compares a company’s current price-to-earnings ratio to a benchmark like its historical average, industry peers, or the broader market. This comparison helps investors evaluate whether a stock is trading at a premium or discount relative to its usual or expected valuation. By providing a contextual framework, the Relative P/E ratio allows for more informed decisions about whether the stock may be overvalued or undervalued based on its position against relevant reference points.
 

Formula:
 

Relative P/E Ratio = (Current P/E Ratio)/(Benchmark P/E)
 

Uses and interpretation: 

• Historical comparison: By comparing the current P/E ratio with historical averages, investors can assess whether the stock is trading at a higher or lower valuation than usual.
• Industry and market comparison: Comparing the P/E ratio to industry or market averages helps investors understand how the company is valued relative to its peers or the overall market.
• Contextual valuation: The relative P/E ratio provides a more nuanced view of valuation, accounting for broader market conditions and industry trends.

Example: If a company has a current P/E ratio of 20, the historical average P/E ratio is 15, the industry average is 18, and the overall market average is 25:

• Relative to historical average: 2015=1.331520​=1.33 (The current P/E is 33% higher than its historical average)
• Relative to industry average: 2018=1.111820​=1.11 (The current P/E is 11% higher than the industry average)
• Relative to market average: 2025=0.802520​=0.80 (The current P/E is 20% lower than the market average)

Understanding both Absolute and Relative P/E ratios allows investors to make more informed decisions by not only assessing the intrinsic value of a stock but also placing that valuation in the broader context of historical performance, industry standards, and overall market conditions.

Value investors prioritise the intrinsic value of a company's underlying assets over its current market price. The Price-to-Earnings (P/E) ratio is a crucial tool in this approach, helping to identify potential mispricings.
 

A high P/E ratio suggests that a company's share price is significantly higher relative to its earnings, potentially indicating an overvalued stock. Value investors generally avoid such stocks, as they may be subject to speculative bubbles and prone to significant price corrections.
 

A below-average P/E ratio might suggest that a stock is undervalued, potentially offering a good buying opportunity. However, it is important to compare P/E ratios within the same industry, as valuation standards can vary significantly across different sectors. Contextual analysis ensures more accurate investment decisions.
 

Value investing typically requires a long-term investment horizon to fully realise its potential returns.

What is a good PE ratio?

A good P/E ratio depends on context, not just its value. With the market average between 20–25, a higher P/E may signal overvaluation, while a lower one may suggest value important to recognise that the "goodness" of a P/E ratio is contingent upon various factors, including prevailing market conditions, industry averages, and the specific nature of the business.
 

To make informed comparisons, investors should assess how a company's P/E ratio stacks up against peers within the same industry, with similar characteristics and growth trajectories. For example, a company with a P/E ratio of 40 is trading at a significantly higher premium compared to a peer with a ratio of 10. This suggests that investors are willing to pay more for each rupee of earnings in the former company.
 

While high P/E ratios may signal potential overvaluation, low ratios could indicate suboptimal performance or underlying issues. Therefore, relying solely on this ratio for investment decisions can be risky. To gain a more comprehensive understanding, investors should consider additional financial metrics such as discounted cash flow and weighted average cost of capital.
 

Using P/E ratios to determine investment strategies

The P/E ratio can help shape long-term investment decisions by offering insight into how a stock is valued relative to its earnings. A higher ratio often shows that investors are paying more for future expectations, even when current profits are lower, which can later result in price corrections. On the other hand, a lower ratio may indicate that the market is undervaluing the company, creating scope for gradual price appreciation as its prospects improve.
 

For meaningful analysis, it is advisable to compare companies within the same industry. There is no universal standard for an ideal P/E ratio, but a figure above the industry average may suggest overvaluation, while a lower ratio could point to relative undervaluation.
 

Sector-wise PE ratios: Comparing companies using the P/E ratio

There is no absolute cut-off for determining a good P/E ratio from a bad one. Instead, a more effective strategy is to compare the price-to-earnings ratios of two different companies within the same industry or sector to get more clarity about their valuation. If the price-to-earnings ratio for a company is higher than the sectoral average, it may be indicative of overvaluation (and vice versa).
 

Limitations of the P/E ratio

Despite the many insights you can get with the P/E ratio in the share market, this metric has its limitations. They include the following:
 

• The ratio does not factor in a company’s debts.
• It does not give you insights about the company’s cash flow.
• You do not learn any material information about the quality of the company’s earnings.
• It is not very effective for comparing companies in different sectors or industries.

Value investors prioritise the intrinsic value of a company's underlying assets over its current market price. The Price-to-Earnings (P/E) ratio is a crucial tool in this approach, helping to identify potential mispricings.

A high P/E ratio suggests that a company's share price is significantly higher relative to its earnings, potentially indicating an overvalued stock. Value investors generally avoid such stocks, as they may be subject to speculative bubbles and prone to significant price corrections.

A below-average P/E ratio might suggest that a stock is undervalued, potentially offering a good buying opportunity. However, it’s important to compare P/E ratios within the same industry, as valuation standards can vary significantly across different sectors. Contextual analysis ensures more accurate investment decisions.

Value investing typically requires a long-term investment horizon to fully realise its potential returns.

Conclusion

The bottom line is that a company’s P/E ratio is not a foolproof indicator of its valuation. It is best to combine this ratio in the share market with other indicators and ratios like the price-to-sales ratio, price-to-book ratio, debt-to-equity ratio, and dividend yield. This will give you a comprehensive overview of the company’s future prospects.