FERTILITY TRENDS, POPULATION POLICIES IN SOCIALIST EUROPE 67 diate post-war period attained peaks in different years in the different countries.3 In Bulgaria and Czechoslovakia the post-war peaks were attained in 1946-47. The peaks in Romania, Hungary and Poland were attained a bit later, in 1949 in Romania, in 1951 in Poland and in 1954 in Hungary. In all the countries except Romania, these postwar peaks were well above the crude birth rates registered before the war.4 In Romania, despite the peak of 1949, the historical downward trend ih crude birth rates that had begun before the war was not reversed. The crude birth rate in 1980 expressed as a percentage of the crude birth rate in 1950 was 57.5 per cent in Bulgaria, 69.5 per cent in Czechoslovakia, 86.4 per cent in the G.D.R., 66.5 per cent in Hungary, 63.5 per cent in Poland, 68.7 per cent in Romania and 56.3 per cent in Yugoslavia. In proportionate terms, the greatest declines since 1950 have thus been in Bjigaria and Yugoslavia and the least in the G.D.R. The extent of inter-country differentials in crude birth rates across the region has also declined. Comparing across countries, the ratio of the lowest to the highest crude birth rate was 0.55 in 1950 and 0.71 in 1980. There are considerable intra-country variations in crude birth rates. Apart from the obvious urban/rural differenntial, there are also interregional differences in crude birth rates. In Czechoslovakia, crude birth rates in relatively underdeveloped and Catholic Slovakia have been higher than crude birth rates in the relatively developed and Protestant Czech lands.5 With the industrialisation of Slovakia, this difference has however narrowed over time. In Yugoslavia, crude birth rates have declined very little in the less developed region of Kosovo and next highest crude birth rates are exhibited by the moderately developed regions of Bosnia-Hercegovina and Macedonia. The lowest crude birth rates are in the more developed regions of Croatia, Slovenia, Serbia proper and Vojvodina.6 The onset of the period of demographic transition has thus varied across Yugoslavia's republics and autonomous provinces. ^ The crude birth rate is of course a very superficial indicator of fertility, since it is also influenced by changes in the age and sex composition of the population. More specifically, the crude birth rate can be split up into its three components of a general fertility rate, the proportion of women in the reproductive age-groups to the total female populatiuon, and the proportiuon of women in the total population.7 Changes in age-compositions have had two distinct effects on post-war crude birth rates.8 In the first place, especially in the G.D.R. and Poland, war losses distorted age compositions so that the size of the cohorts which reached reproductive age in the early and mid-sixties was greatly reduced. This had a clear negative effect on the crude birth rates. In the second place, larger cohorts born in the immediate postwar baby boom started to enter reproductive ages in the late sixties and early seventies. This had a clear positive effect on crude birth rates. A third factor, that of a general ageing of the population, came into play in the late seventies and early eighties. General fertility, as measured