Age trends in mean nonpregnant weight of CLHNS women according to baseline age groups. Points represent the mean weight of women at the mean age for the age group in each survey year (1984, 1985, 1986, 1991, 1994, 1998, 2002, 2005). The vertical dotted line illustrates the difference in estimated weight for a woman who was 40 y old in 1985 compared with a woman who was aged 40 y in 2005.