• One percent of all the world's commercially used wood—totaling 17.8 million cubic yards in 2012—is used to make IKEA products.

• One in two babies in America today is born to an unwed mother. In 1980, the number was one in five.

• One percent of Americans live in Iowa; so do 31 percent of American pigs.

• One disease—diabetes—accounts for 13 percent of all U.S. medical-care spending, a total of $176 billion last year.

• One counselor is employed for every 1,016 public-school students in California. That is the highest ratio in the U.S., and more than double the national average.

Sources: IKEA; National Center for Family & Marriage Research; U.S. Census Bureau; U.S. Department of Agriculture; American Diabetes Association; American School Counselor Association.