The core-age labour force

From 1995 to 2004, the proportion of women and men aged 25 to 54 in the labour force grew steadily. However, from 2004 into the first half of 2006, both women's and men's participation rates declined very slightly yet persistently. Is this the beginning of a new trend or does it merely reflect regular fluctuations in the economy? Particular attention is focused on women with young children.