What lesson would you draw from numbers like divorce rates anyway? Say children from single-sex schools grow up to be in relationships that have lower divorce

What lesson would you draw from numbers like divorce rates anyway? Say children from single-sex schools grow up to be in relationships that have lower divorce rates. Does that mean that single-sex schools better prepared them for marriage? Or are they just in unhappy relationships that children that grew up in coed schools would know to end earlier since they've more inter-sex socialization experience?