The term rate can also tell the frequency in which something occurs. In adoption terms, this would be placements. To get a good picture of adoption rates, you need to step back to see the broader picture.
As of August 2018, the world population was over 7.6 billion people. Around 4 million babies are born in the United States each year. According to the Adoption Network statistics, around 140,000 children are adopted by American families each year, and around 62% of babies in domestic infant adoptions were placed with their adoptive families within a month of birth.
Of non-stepparent adoptions, about 59% are from the child welfare (or foster) system, 26% are from other countries, and 15% are voluntarily relinquished American babies. Around 37% percent of adopted children are non-Hispanic white compared with adoptive parents, 73% of which are non-Hispanic white.
Overall, 40% of the adopted children are of a different race, culture, or ethnicity compared to both of their adoptive parents (or their sole parent if there is only one parent in the household).