Once defined, social classes can be considered to feature their own sub-cultures, including different ways of socializing children. Due to class mobility individuals may also acculturate to the culture of another class when ascending or descending in the social order. All social classes in the United States, except the upper class, consist of tens of millions of people. Thus social classes form social groups so large that they feature considerable diversity within and any statement regarding a given social class' culture needs to be seen as a broad generalization.