Social Doctrine of the Church - Family Wage

I have heard folks like these and especially these discuss a different approach to wages than is ordinarily encountered in the U.S. Now I think I see where it has come from.

Family and work are united by a very special relationship. "The family constitutes one of the most important terms of reference for shaping the social and ethical order of human work". This relationship has its roots in the relation existing between the person and his right to possess the fruit of his labour and concerns not only the individual as a singular person but also as a member of a family, understood as a "domestic society".

Work is essential insofar as it represents the condition that makes it possible to establish a family, for the means by which the family is maintained are obtained through work. Work also conditions the process of personal development, since a family afflicted by unemployment runs the risk of not fully achieving its end (Compendium of the Social Doctrine of the Church, 249).

The critical thing to note here is the fact that work makes it possible to establish and maintain a family. The Compendium continues:

In order to protect this relationship between family and work, an element that must be appreciated and safeguarded is that of a family wage, a wage sufficient to maintain a family and allow it to live decently. Such a wage must also allow for savings that will permit the acquisition of property as a guarantee of freedom. The right to property is closely connected with the existence of families, which protect themselves from need thanks also to savings and to the building up of family property (250; emphasis added).

If not drawn directly from it, the passage above rather obviously is inspired by Pope Leo XIII's encyclical Rerum Novarum:

Let the working man and the employer make free agreements, and in particular let them agree freely as to the wages; nevertheless, there underlies a dictate of natural justice more imperious and ancient than any bargain between man and man, namely, that wages ought not to be insufficient to support a frugal and well-behaved wage-earner...

If a workman's wages be sufficient to enable him comfortably to support himself, his wife, and his children, he will find it easy, if he be a sensible man, to practice thrift, and he will not fail, by cutting down expenses, to put by some little savings and thus secure a modest source of income. Nature itself would urge him to this. We have seen that this great labor question cannot be solved save by assuming as a principle that private ownership must be held sacred and inviolable. The law, therefore, should favor ownership, and its policy should be to induce as many as possible of the people to become owners (45, 46).

What annual income would constitute a "family wage" here in the United States? I suppose it would probably vary by geography - it costs a lot less to live in some areas than in others.