The basket
The National Bureau of Statistics tracks the price of a fixed basket of goods every month, across markets in every state. Food inflation is how much the food part of that basket costs compared to the same month last year. Year-on-year, not month-on-month. People mix these up constantly, including on television.
A headline saying 'food inflation is 35 percent' means food costs 35 percent more than twelve months ago. It does not mean prices rose 35 percent this month.
Reading a spike
When tomato prices triple, there are always several suspects: a failed harvest, fuel and transport costs, insecurity in growing regions, the naira, and sometimes plain hoarding. A climate-literate reader asks about timing and geography. A drought-driven spike follows the growing season and hits specific crops from specific regions.
Being able to say 'this spike is mostly weather, that one is mostly fuel' is rare and valuable. It is also the difference between blaming correctly and blaming loudly.
Track it yourself
NBS publishes its CPI report every month, free. Read the food inflation number and the note on which items moved most. Then keep your own record: the price of one item, in one market you actually visit, written down monthly.
Three months of your own notebook will teach you more about data than any chart on the internet, because you will know exactly how the number was made.
Hold on to these
- Food inflation is year-on-year: this month's basket versus the same month last year.
- Price spikes have multiple drivers. Timing and geography reveal the climate share.
- NBS publishes the data monthly, free. Your own market notebook is data too.
Check yourself
No grades here. If you can answer these out loud, you own the lesson.
- 1.A headline says food inflation hit 38 percent. What exactly does that mean?
- 2.What clues suggest a price spike is driven by weather rather than fuel costs?
- 3.Which single item would you track in your local market, and why that one?