The overcrowded area of Hanover (especially with the addition of the neighboring towns and rural communes) has a direct bearing on its economic significance. In this area live approximately 1.07 million inhabitants, which is 14,8 % of the population of Lower Saxony. It produced 19,9 % of the gross domestic produce (1978), 15.7 % of industrial turnover (1981) and 18,5 % of actual tax income (1981) of the whole country. Industrial activity is primarily centered in machinery production, electronic engineering, chemical and rubber production, in which 60 % of those in industry are involved. In addition, as in other economic areas, a change of structure has taken place in favor of service industries. The reason for this is the above average growth of office employment in local authorities and corporations, but primarily the increase in banks and insurance companies. 60 financial institutions with 236 branches are present here. Hanover has, however, not only developed into an important banking center, but as the insurance industry is also starting to take a lead position in the city. No less than 10 insurance companies, have their head office in the capital of Lower Saxony. Greater Hanover and the regional capital with its concentration of dwellers and companies is a strong market for investment and consumer goods. The concentration of retail outlets in Hanover is 136 % higher than in comparable cities in Germany. A special significance is the connection with the Hanover Fair and international trade exhibitions. From humble beginnings in 1947 Hanover has developed into a leading international exhibition center and the Hanover Fair has in fact become the largest industrial show in the world.