Biology Forums - Study Force

Kids today are far more likely to grow up in single-parent homes than ever before.
  Two-parent households have dropped from 40 percent of the total number of family
  households in 1970 to 26 percent in 1990 according to surveys taken of 2,000 households each
  in 1970 and 1990.

(Inductive generalization. The sample consists of 4,000 households. Supposing it to
be a stratified random selection, it provides good reason for concluding that there is
an overall national decline in the number of two-parent households, thus, more likely
that kids will grow up in single-parent homes.)