The primary sector involves:
Economic activities that involve manufacturing and construction are typically classified as part of the secondary sector. It draws on the input from the primary sector to manufacture finished goods that are ready to be used for sale, export or as input for other industries. The manufacturing sector is capital intensive. It requires a production unit and investment in technology to earn profits. A large amount of exports usually generates favorable trade and high GDP figures.
Some of the major industries in the secondary sector are:
The tertiary sector involves services that supplement the production and sale of goods, such as transportation, retail sale and distribution. Other specific services include legal practice, entertainment and medical services.
A number of economists also propose the theory of a quaternary sector to span information services, education and research and development
The country industry data and GDP composition spanning varied sectors across different nations are listed in the table below. The data is gathered from the CIA World Factbook, 2008.
| Country | Agriculture (%) | Industry (%) | Services (%) |
| Brazil | 5.5 | 28.5 | 66 |
| Canada | 2 | 28.4 | 69.6 |
| China | 10.6 | 49.2 | 40.2 |
| France | 2.2 | 20.3 | 77.4 |
| Germany | 0.9 | 30.1 | 69 |
| India | 17.2 | 29.1 | 53.7 |
| Italy | 2 | 26.7 | 71.3 |
| Japan | 1.4 | 26.4 | 72.1 |
| Russia | 4.1 | 41.1 | 54.8 |
| US | 1.2 | 19.6 | 79.2 |
| UK | 0.9 | 22.8 | 76.2 |
Countries with the largest GDP share indicate a weak primary sector and a huge share in the service industry. In developing countries, however, agriculture is the largest contributor to the GDP. Their focus, in terms of economic growth, should be to make their presence felt more effectively in the service industry.