One big reason is the soaring cost of ushering offspring to functional independence.
The share of mothers employed full or part time has quadrupled since the 1950s and today accounts for nearly three-quarters of women with children at home.
The number of women who are their families’ sole or primary breadwinner also has soared, to 40 percent today from 11 percent in 1960.
They describe themselves as mild-mannered introverts who suffer from an array of chronic medical problems. On their wedding day in 2011, the groom was 43 years old and the bride 39, yet it was marriage No. Today, their blended family is a sprawling, sometimes uneasy ensemble of two sharp-eyed sons from her two previous husbands, a daughter and son from his second marriage, ex-spouses of varying degrees of involvement, the partners of ex-spouses, the bemused in-laws and a kitten named Agnes that likes to sleep on computer keyboards.
They love crossword puzzles, football, going to museums and reading five or six books at a time.
More than one-quarter of these unwed mothers are living with a partner who may or may not be their child’s biological father.
The rise of the cohabiting couple is another striking feature of the evolving American family: From 1996 to 2012, the number jumped almost 170 percent, to 7.8 million from 2.9 million.
We lavish billion a year on weddings, more than we spend on pets, coffee, toothpaste and toilet paper combined. When an informal sample of 52 Americans of different ages, professions and hometowns were asked the first thought that came to mind on hearing the word “family,” the answers varied hardly at all. At the end of the baby boom, in 1964, 36 percent of all Americans were under 18 years old; last year, children accounted for just 23.5 percent of the population, and the proportion is dropping, to a projected 21 percent by 2050.
Fewer women are becoming mothers — about 80 percent of those of childbearing age today versus 90 percent in the 1970s — and those who reproduce do so more sparingly, averaging two children apiece now, compared with three in the 1970s.
The typical American family, if it ever lived anywhere but on Norman Rockwell’s Thanksgiving canvas, has become as multilayered and full of surprises as a holiday turducken — the all-American seasonal portmanteau of deboned turkey, duck and chicken.