Internal Growth Rate Calculator
Understand and calculate your business's organic growth potential.
Enter the following values to calculate the Internal Growth Rate (IGR).
What is the Internal Growth Rate (IGR)?
The Internal Growth Rate (IGR) is a financial metric that measures how much revenue a company can generate using its existing assets and without relying on external financing. It essentially calculates the maximum rate at which a company can grow its sales by reinvesting its own profits. Understanding your internal growth rate is crucial for assessing the organic growth potential and financial health of your business. It provides insights into how effectively a company is utilizing its resources to expand.
Businesses that primarily use retained earnings to fund their growth will find the IGR particularly relevant. It helps management set realistic growth targets and identify potential funding gaps if their desired growth exceeds what can be achieved internally. This metric is often contrasted with the Sustainable Growth Rate (SGR), which considers the company's target debt-to-equity ratio as well.
A common misunderstanding surrounds the IGR is that it represents the *total* potential growth. In reality, it's the growth achievable *solely* through internal means, excluding new debt or equity. Another point of confusion can be the unit of measurement; IGR is always a percentage and is unitless in its final form, though intermediate calculations may involve monetary values.
Internal Growth Rate (IGR) Formula and Explanation
The core formula for the Internal Growth Rate (IGR) relies on the company's profitability and its ability to retain earnings. It's calculated using the Return on Assets (ROA) and the retention ratio (the proportion of net income reinvested back into the business).
The formula is:
IGR = (ROA * b) / (1 – ROA * b)
Where:
- ROA (Return on Assets): Measures how profitable a company is relative to its total assets. It's calculated as Net Income / Total Assets. In this calculator, ROA is derived from the profit margin and the assets-to-equity ratio.
- b (Retention Ratio): The percentage of net income that is not paid out as dividends but is reinvested in the company. It's calculated as (Net Income – Dividends) / Net Income, or more simply 1 – Payout Ratio.
To simplify calculation within this tool, we derive ROA and then calculate the retention ratio 'b' from the provided profit margin and assets-to-equity ratio.
Intermediate Calculations:
- Revenue Growth Rate: This is the basic year-over-year (or period-over-period) percentage increase in revenue.
Formula:((Current Revenue - Previous Revenue) / Previous Revenue) * 100% - Return on Assets (ROA): Calculated as Profit Margin * (Total Assets / Total Equity), effectively Profit Margin * Assets-to-Equity Ratio.
- Retention Ratio (b): Assumed to be 100% if no dividends are paid or external financing is used for growth. In many simplified IGR calculations, it's assumed that all profits are retained. Our calculator uses the profit margin to approximate the reinvested portion of revenue relative to assets.
- Sustainable Growth Rate (SGR): This is the maximum growth rate a company can achieve without increasing its financial leverage (debt-to-equity ratio).
Formula:ROE * b, where ROE is Return on Equity. Since ROE = ROA * (Assets/Equity), SGR = (ROA * (Assets/Equity)) * b.
Variable Table:
| Variable | Meaning | Unit | How Calculated/Provided |
|---|---|---|---|
| Current Revenue | Total revenue for the current period. | Currency (e.g., USD, EUR) | User Input |
| Previous Revenue | Total revenue for the prior period. | Currency (e.g., USD, EUR) | User Input |
| Profit Margin | Percentage of revenue that is profit (Net Income / Revenue). | Percentage (%) | User Input (e.g., 15 for 15%) |
| Assets to Equity Ratio | Total Assets / Total Shareholders' Equity. Measures financial leverage. | Unitless Ratio | User Input (e.g., 2.0) |
| ROA | Return on Assets. Profitability relative to total assets. | Percentage (%) | Calculated: (Profit Margin / 100) * Assets to Equity Ratio * 100 |
| Retention Ratio (b) | Proportion of net income reinvested. Assumed 100% for IGR unless otherwise specified. | Percentage (%) | Assumed 1.0 (100%) for IGR calculation in this tool. |
| ROE | Return on Equity. Profitability relative to shareholder's equity. | Percentage (%) | Calculated: ROA * Assets to Equity Ratio |
| IGR | Internal Growth Rate. Max growth from retained earnings. | Percentage (%) | Calculated using ROA and b. |
| SGR | Sustainable Growth Rate. Max growth without leverage change. | Percentage (%) | Calculated using ROE and b. |
Practical Examples of Internal Growth Rate
Let's illustrate with a couple of scenarios:
Example 1: A Stable, Profitable Tech Company
A software company has the following figures:
- Current Period Revenue: $5,000,000
- Previous Period Revenue: $4,000,000
- Profit Margin: 20%
- Assets to Equity Ratio: 1.5
Using the calculator:
- Revenue Growth Rate: (($5,000,000 – $4,000,000) / $4,000,000) * 100% = 25%
- ROA: (20% / 100) * 1.5 * 100 = 30%
- Retention Ratio (b): Assumed 1.0 (100%)
- IGR: (0.30 * 1.0) / (1 – 0.30 * 1.0) = 0.30 / 0.70 = 42.86%
- ROE: 30% * 1.5 = 45%
- SGR: 45% * 1.0 = 45%
Interpretation: This company can theoretically grow its revenue by up to 42.86% using only its retained earnings. Its sustainable growth rate is slightly higher at 45%, indicating it can maintain its current leverage while growing at that pace.
Example 2: A Manufacturing Firm with Lower Margins
A manufacturing company reports:
- Current Period Revenue: $10,000,000
- Previous Period Revenue: $9,000,000
- Profit Margin: 8%
- Assets to Equity Ratio: 2.5
Using the calculator:
- Revenue Growth Rate: (($10,000,000 – $9,000,000) / $9,000,000) * 100% = 11.11%
- ROA: (8% / 100) * 2.5 * 100 = 20%
- Retention Ratio (b): Assumed 1.0 (100%)
- IGR: (0.20 * 1.0) / (1 – 0.20 * 1.0) = 0.20 / 0.80 = 25%
- ROE: 20% * 2.5 = 50%
- SGR: 50% * 1.0 = 50%
Interpretation: This firm's internal growth capacity is 25%. While its revenue growth was 11.11%, its profitability and leverage allow for significant potential expansion through reinvestment. The SGR is much higher, suggesting it could grow faster if it maintained its leverage.
How to Use This Internal Growth Rate Calculator
- Gather Financial Data: Collect the revenue figures for the current and previous periods, the company's profit margin, and its assets-to-equity ratio.
- Input Values: Enter the Current Revenue and Previous Revenue in your preferred currency. For Profit Margin, enter the percentage value (e.g., '15' for 15%). For the Assets to Equity Ratio, enter the numerical ratio (e.g., '2.0').
- Calculate: Click the "Calculate IGR" button.
- Review Results: The calculator will display the Internal Growth Rate (IGR), Revenue Growth Rate, and Sustainable Growth Rate (SGR).
- Interpret: Understand that the IGR shows growth potential from retained earnings alone. Compare it to your actual revenue growth and SGR to identify opportunities or constraints.
- Reset: Use the "Reset" button to clear the fields and start a new calculation.
- Copy Results: Click "Copy Results" to easily transfer the calculated figures.
Ensure you use consistent periods (e.g., annual revenue for both current and previous) and the same currency for accurate results. The 'Assets to Equity Ratio' is critical; a higher ratio implies greater leverage, which can amplify returns but also risk.
Key Factors That Affect Internal Growth Rate
- Profitability (Net Profit Margin): Higher profit margins mean more earnings are generated per dollar of sales, providing a larger base for reinvestment. A 10% increase in profit margin can significantly boost IGR.
- Asset Utilization (ROA): How efficiently a company uses its assets to generate profit directly impacts IGR. Better asset management leads to higher ROA and thus higher IGR.
- Retention Ratio (b): The decision to retain earnings versus paying dividends is paramount. A 100% retention ratio maximizes IGR, assuming no external financing. Any payout reduces this capacity.
- Financial Leverage (Assets-to-Equity Ratio): While IGR focuses on internal financing, ROA is derived using assets. A higher assets-to-equity ratio magnifies ROE (and thus SGR), but IGR calculation uses ROA which is less directly impacted by leverage itself, though leverage influences the *components* of ROA (Net Income / Total Assets). The relationship is complex, but efficiency in asset deployment remains key.
- Dividend Policy: Companies that pay out a large portion of their earnings as dividends inherently limit their internal growth capacity.
- Operational Efficiency: Streamlining operations, reducing costs, and improving productivity all contribute to higher profit margins and better asset utilization, indirectly boosting IGR.
- Industry Norms: Different industries have varying typical profit margins and asset intensities. A comparison should consider industry benchmarks.
Growth Visualization
Visual comparison of Revenue Growth, IGR, and SGR.
Frequently Asked Questions (FAQ)
IGR calculates the maximum growth achievable using only retained earnings. SGR calculates the maximum growth achievable while maintaining a constant debt-to-equity ratio, allowing for external debt financing.
Yes, a company can grow faster than its IGR if it secures external financing (debt or equity) or sells off assets. However, IGR represents growth achievable *without* these external factors.
A "good" IGR varies significantly by industry. Generally, a higher IGR indicates a stronger capacity for organic growth. Comparing your IGR to industry averages and your own historical performance is most insightful.
No, the standard IGR formula does not explicitly account for inflation. Growth rates are typically analyzed in nominal terms. For real growth, you would need to adjust the revenue figures for inflation.
While IGR is primarily driven by ROA and retention ratio, a higher Assets to Equity ratio increases ROE. This means the company relies more on debt. For IGR specifically, ROA is key, but the overall financial health and risk profile associated with high leverage are important considerations.
This indicates negative revenue growth. The Revenue Growth Rate will be negative. Your IGR calculation will still proceed based on profitability and asset ratios, showing your potential for growth even if you are currently experiencing a downturn.
Yes, as long as you are consistent. If you use monthly revenue, ensure your profit margin and asset ratios are representative of that period or adjusted accordingly. Annual data is more common for strategic planning.
A negative IGR is mathematically impossible with positive ROA and a retention ratio of 1 (meaning all profits are reinvested). If the ROA calculation results in a negative value (due to losses), the formula might yield unusual results or indicate severe unprofitability, suggesting the company cannot grow internally.