The expenditure approach to GDP
Gross domestic product measures the total value of everything an economy produces over a period. The expenditure approach reaches that total by adding up who buys the output rather than who makes it. It groups all spending into four buckets and sums them.
The four are household consumption (C), business investment in things like equipment and buildings (I), government spending on goods and services (G), and net exports — what the country sells abroad minus what it buys from abroad (X − M). Add the first three and adjust for trade, and you have GDP.
Why net exports can be negative
Net exports is the only component that can subtract from GDP. When a country imports more than it exports, X − M is negative, pulling the total down. That makes sense under this approach: imports are spending that flows out to foreign producers, so they are removed to leave only domestically produced output.
The chart lays the four components side by side so you can see which drives the economy and whether trade adds to or drags on the total. In most large economies consumption is by far the biggest bar.
Reading and using the result
The headline GDP is the sum of the components; net exports is reported separately so you can see the trade balance on its own. A few cautions when interpreting the figure:
- This is nominal GDP — it is not adjusted for inflation, so comparing across years can mislead unless you convert to real terms.
- GDP measures output, not wellbeing; it ignores distribution, unpaid work, and environmental cost.
- The same total can be reached by the income or production approaches, which should agree in principle.
- Make sure every component is in the same currency and time period before summing.
Formula
GDP = C + I + G + (X − M)Frequently asked questions
- Why can net exports be negative?
- When a country imports more than it exports, net exports (X − M) are negative, which reduces GDP under the expenditure approach.