The "surge in births to unmarried black women" is mostly myth. There's a
nice graph which shows the birth rate to unmarried women, by race
black and white, and by age group, at
http://www.ed.gov/pubs/YouthIndicators/indfig07.gif
and the detailed data can be found at
http://www.ed.gov/pubs/YouthIndicators/indtab07.html
The birth rate to unmarried black women peaked in 1960, fell throughout
the 1960s and 1970s, and has been approximately flat since then. The
1990 figure is about the same as the 1975 figure. For unmarried black
teenagers, the series peaked in 1970, fell a little, rose a little, and
is about where it was in 1970. Other age groups show declines since
1960.
The overall (all races) is up somewhat because of the rise in
the birth rate to unmarried white women.
There is a much bigger fall, for both black and white, in the
marriage rate, which means that births to married women have dropped
drastically. Therefore the fraction of total births to unmarried women
has risen.
The interesting question is why the marriage rate has fallen.
There's a nice graph showing the precipitous drop in the marriage rate at
http://www.ed.gov/pubs/YouthIndicators/indfig03.gif
Dale Tussing
