What it measures
Net profit margin is net income divided by revenue, expressed as a percentage. A 20% net profit margin means the company keeps 20 kobo of every naira it brings in, after every expense, tax, and cost of goods sold is accounted for.
Margins vary hugely by industry on their own terms, a grocery-adjacent business often runs thin single-digit margins on purpose, while a software or services business commonly runs much higher ones. The number alone means less than the number against its own sector.
A worked example
A company reports revenue of 5 billion and net income of 750 million for the same period. Net profit margin: 750,000,000 / 5,000,000,000 = 15%.
How Kobo & Cents uses it
Net profit margin sits in the profitability category with Return on Equity and Return on Invested Capital. All three get compared against sector peers, never against a flat, one-size-fits-all benchmark.