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>I think there are two factors here. One is that lots of people are marrying later (and, in fact, there's a correlation between education levels and age at marriage, and between age at marriage and lifetime income, the latter especially for women). (http://twentysomethingmarriage.org/in-brief/)
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>The other, I think, is that there's no longer an imperative to marry when a girl becomes pregnant. Used to be that if a boy got a girl pregnant, he married her. Not so much any more.
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I agree with both of those observations.
However, the wisdom of those choices is the question.
If the number of people starting life with one parent has mushroomed, and the current divorce rate in the US is more than twice rate for marriages during the 50's and 60's, how are those good choices?.