The second unexpected change is the turnround in the pattern of net migration . Prior to about 1970 there was a positive correlation between the population size of a settlement (conceived here in labour market area terms ) and its net migration the smaller , the small , more rural or more isolated a place was the more likely it was to lose population through internal migration, and the larger, more urban or more central a place was , the more likely it was to galn through internal migration. It might have been expected that this pattern would have continued after 1970 because the employment shift away from agriculture and towards the services continued, as did the advantage of metropolitan areas over areas with respect to wage levels and levels of unemployment . Again this did not happen. The relationship between size of settlement and net migration became a negative one,the largest cities lost and the smaller towns and rural areas gained ( Court.