<Tr> <Td> Spain </Td> <Td> Sweden </Td> <Td> Switzerland </Td> <Td> United Kingdom </Td> <Td> United States </Td> </Tr> <P> The World Systems Theory argues that a nation's future is decided by their stance in the global economy . A global capitalistic market demands the needs for wealthy (core) states and poor (periphery) states . Core states benefit from the hierarchical structure of international trade and labor . World systems theory follows the logic that international wars or multinational financial disputes can be explained as attempts to change a location within the global market for a specific state or groups of states; these changes can have the objective to gain more control over the global market (to become a core country), while causing another nation to lose control over the world market . As the two groups grew apart in power, world systems theorists to established another group, the semi-periphery, to act as the middle group . </P> <P> Semi-periphery countries usually surround the core countries both in a physical and fundamental sense . The semi-periphery countries act as the middle men between the core and the periphery countries - by giving the wealthy countries what they receive from the poor countries . The periphery countries are the poorer countries usually specializing in farming and have access natural resources - which the core countries use to profit from . </P> <P> In order for a country to remain a core or to become a core, possible investors must be kept in mind when nation's policies are planned . Core countries change with time due to many different factors including changes in geographic favoritism and regional affluence . Alterations in financing plans by companies will also play a part as they change to react to the continuously evolving world market . </P>

Which type of economic system do most western countries have