The nature of adoption statistics have changed since the U.S. Census Bureau included its first adoption questions on the 2010 Census. There are roughly 1.5 to 2 million child adoptees in America and anywhere from 6 to 10 million adult adoptees.
While most of the behavioral research that can give insight into the social facet of adoption, such as contentment of adoptees in open adoptions or contributing factors to a birth mother backing out of a placement, are dated studies that can be found but may not be fully accurate in this quickly changing world of adoption.
In July 2010, the Children's Bureau's Administration for Children and Family (AFCARS)estimated that there were almost half a million children in the U.S. foster care system. Half of those children entered into the system only a year prior. The number of children adopted from the foster care system has increased slowly in the last decade, though.
While foster adoption has increased, international adoption has actually fallen to numbers that hadn't been seen in since 1996, with only 11,000 international adoptions taking place in 2010.
For more foster statistics, visit the Children's Bureau's Administration for Children and Families (acf.hhs.gov). For international adoption statistics, visit the Bureau of Consular Affairs (adoption.state.gov). For a collection of recent and dated adoption research, visit the Child Welfare Information Gateway (childwelfare.gov).