Analyzing and interpreting income statements in commerce requires a systematic approach and understanding of key financial indicators. Here are some steps you can follow:

1. Understand the structure of an income statement: Familiarize yourself with the components of an income statement, including revenues, expenses, net income, and earnings per share.

2. Review the revenue section: Look at the sources of revenue and identify any significant changes or trends. Compare revenue figures to previous periods or industry benchmarks to assess the company's performance.

3. Analyze the cost of goods sold (COGS): COGS represents the direct costs associated with producing or delivering the company's products or services. Evaluate any changes in COGS and compare it to revenue growth to determine the company's ability to manage costs.

4. Assess operating expenses: Analyze the various operating expenses, such as marketing, research and development, and general administrative costs. Look for any significant changes or deviations from historical patterns and industry standards.

5. Calculate and interpret profitability ratios: Calculate key profitability ratios like gross profit margin, operating profit margin, and net profit margin. These ratios can help you understand the company's profitability relative to its revenue and expenses.

6. Evaluate non-operating income and expenses: Non-operating items such as interest income, interest expense, and gains or losses from investments can impact the overall financial performance. Assess these items separately to understand their impact on the company's bottom line.

7. Analyze earnings per share (EPS): EPS indicates the portion of the company's profit allocated to each outstanding share of common stock. Compare the company's EPS with previous periods or industry benchmarks to assess its growth and profitability.

8. Consider qualitative factors: While numbers provide valuable insights, consider qualitative factors such as industry trends, competitive landscape, and management's commentary on the income statement. These factors can help provide a more holistic understanding of the company's financial performance.

9. Compare to peers and industry benchmarks: Benchmark the company's income statement against its competitors or industry averages to identify areas of strength or weakness. This comparison can provide valuable insights into the company's relative performance.

10. Seek professional guidance if needed: If you are unsure about any aspect of the income statement analysis, consider consulting with a financial professional or accountant who can provide further guidance and interpretation.

Remember, analyzing income statements is just one part of a comprehensive financial analysis. It is crucial to consider other financial statements such as the balance sheet and cash flow statement for a complete understanding of a company's financial health.