During the last thirty years, the international economy has experienced a basic change．Improvements in the Internet and other communications have had important effects on world markets．Faster methods of transport from one place to another have made the world seem smaller to the businessmen．As a result, the world no longer．consists of a number of separate economies under the control of different nations．Instead, the nations have been integrated into a single economy, and the integration is becoming more and more complete every year．For the first time in history, we can truly speak of a global economy.
The most dramatic example of this integration was the oil cr of 1973 and 1974．It came as a great surprise to the public in the industrial nations to discover that they depended so heavily on imported oil．However, the best evidence for the growing integration is the rapid expansion in the volume of world trade．It went up by about 7% a year during the decade from 1990 to 2000, and in several quasi-industrial (半工业的) countries the growth was even more rapid．As a result, some imported products have become as common as domestic commodity．Some of them are too common for the public to any more realize they are foreign.
Production has also become international, which is manifested by the large corporations stepping across national borders and established branches and subsidiaries in several different countries．As an example, U.S．companies are building automobiles in Canada, Germany, Britain and Japan．In some cases, components of an automobile are produced abroad and shipped to the United States, where it is then finished with the imported parts．When even the United States has the largest number of such corporations, it is not the only．Other multinationals, for instance, are based in Japan, France, Germany, the UK and Italy.
Labor, too, is much more mobile than in the past．Both skilled and unskilled workers can now readily migrate from one country to another．In Europe, for example, there are large numbers of Turkish workers employed in the Germany Economy．Doctors, lawyers, and other professionals are also finding it easier to work in foreign countries．The labor market has become international, and the number of expatriate workers is continuing to grow.
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