The decline in marriage rates, changes in children’s living arrangements, rise of cohabitation–as well as how the American public feels about these and other changes in family life–are explored with Census data and a public opinion survey in a new report from the Pew Research Center. The report finds that Americans have mixed feelings of acceptance and unease about the changes they see in society, but are optimistic about the future of marriage and the family.

The report from the center’s Social & Demographic Trends project, “The Decline of Marriage and Rise of New Families,” finds that nearly four-in-ten Americans (39%) say that marriage is becoming obsolete, according to findings of a survey conducted in partnership with TIME. This finding takes place in a demographic context of declining marriage rates: According to Census Bureau data, only 52% of adults ages 18 and older were married in 2008, compared with 72% in 1960. Marriage has declined among all groups, but especially so among Americans on the lower rungs of the socio-economic ladder. Increasingly, a “marriage gap” has emerged in which adults with college educations and good incomes are notably more likely to be married than are adults with less education and lower incomes.

The report presents detailed findings about attitudes of men and women, race and ethnic groups, age groups and people who live in different types of family arrangements. It also analyzes demographic data that illuminate changes in the American family in recent decades.