Nineteenth - Century Fertility Oscillations.

The article analysis short-run variations in marital fertility in Sweden during the period 1830-1879 in order to explore different models of fertility determination before the secular decline of fertility took place, and to use fertility data to demonstrate a method of studying sociological trends and oscillations. One of the main determinants of aggregate marital fertility, the total number of legitimate births or the legitimate birth rate, is the number of marriages, and fluctuations in that number. It will be shown that if this were the sole determinant the result would be a very high degree of smoothness in the response, fertility. Auto-correlations would be high, much higher than actually observed. So a simple inspection of the response series and the correlogram is sufficient to reject this explanation, even if there were no direct statistical information on the annual number of marriages. But as direct information on marriages is available, this may be used to compute the expected level of aggregate marital fertility assuming a constant fertility schedule by duration of marriage. This turns out to follow the smooth pattern predicted, whilst observed fertility shows much more pronounced short-term variations.