Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What was the gdp of the country with a gdp per capita of $18048?

### Inputs:
table_name: table, columns: ['Member countries', 'Population', 'Area (km²)', 'GDP (billion US$)', 'GDP per capita (US$)']

### Response:
SELECT GDP (billion US$) FROM table WHERE GDP per capita (US$) = 18048