The Swedish baby boom and bust of 1985-1996 revisited: the role of tempo, quantum and variance effects

Variance effects, i.e., increases in the standard deviation of the fertility schedule over time, constitute a systematic and interesting aspect of recent fertility patterns in Europe. In this paper we investigate the relevance of these variance change for the evaluationof Swedish baby boom and bust in terms of tempo and quantum effects. Using an extension of the adjusted TFR that incorporates variance changes, we show that there was no reduction in the pace of postponement of first births in Sweden during the period 1980-1995. Thus, the baby boom was overwhelmingly due to quantum effects, and did not have a relevant tempo component as suggested by the TFR-adjustment without variance effects. Moreover, the tempo changes duringthis period clearly reflect the implications of the policy changes in the 1980s: while the tempo for first births remained relatively constant, the tempo at higher orders was reduced substantially after the extension of policies that favor short interbirth intervals. However, this pattern is not visible in the tempo effects without adjestment for variance effects. We therefore argue that variance effects deserve further attention in the investigation of recent fertility patterens and in the adjustment of total fertility rate. (AUTHOR)