You may already know that 291 Swedes...

You may already know that 291 Swedes voted for Donald Duck in that country’s last election. But do you know the life span of a sidewalk tree in New York City? Or what the chances are that a female graduate student in psychology has had sex with one of her professors? The answers can be found in the May’s Harper’s Index.

Percentage of Costa Ricans who say that Nicaragua interferes “too much” in Costa Rica’s internal affairs: 40.

Percentage who say that the United States interferes too much: 50.

Percentage change in U.S. imports from Caribbean nations in 1985: minus 22.

Portion of the coffee exported by Nicaragua that is produced by private growers: two-thirds.

Number of banks in the West that are owned by the Soviet Union: 6.

Portion of the Soviet Union’s urban population that shares a kitchen and a bathroom with another family: one-fifth.

Estimated number of Americans who live on communes: 40,000.

Number of Americans who served in Vietnam and were declared missing in action: 2,436.

Number of Americans who were declared missing in action in World War II: 78,751.

Number of federal commissions appointed since 1949 to study the Pentagon: 35.

Number of U.S. university scientists who have pledged to refuse “Star Wars” research funds: 3,100.

Percentage of college freshmen who are enrolled in a remedial math class: 25.

Decimal places to which the value of pi has been calculated: 29,360,128.

Chances that a female graduate student in psychology has had sex with one of her professors: 1 in 6.

Chances that a white, college-educated 25-year-old woman will marry: 1 in 2.

Chances that a white, college-educated 35-year-old woman will marry: 1 in 18.

Percentage of male executives who become fathers by age 40: 90.

Percentage of women between the ages of 20 and 24 in 1965 who were infertile: 4.

Percentage of women between the ages of 20 and 24 who are infertile today: 11.

Rank of Alaska and Utah, among all states, in birthrate: 1 and 2.

Number of European countries whose population is declining: 18.

Percentage of abortions in the United States that are performed on Catholic women: 29.

Number of times the average man sees his parents each year: 47.

The average woman: 62.

Percentage of Americans over 60 who live with a younger relative: 6.3.

Percentage of Japanese over 60 who do: 70.

Percentage increase in the number of middle-class black families in the United States since 1970: 17.

Percentage increase in marriages between blacks and whites since 1977: 33.

Portion of black mayors who head cities that don’t have a black majority: one-third.

Estimated amount spent in all U.S. political campaigns in 1984: $1.8 billion.

Number of votes Donald Duck received in the 1985 Swedish parliamentary elections: 291.

Mary Lou Retton’s “Performer Q” popularity rating in 1984: 53.

Today: 39.

“Product categories” for which the 1988 Olympic organizers are selling official sponsorships: 44.

Corporate sponsors of the recent dog-sled expedition to the North Pole: 65.

Weight of the average male bear in Alaska (in pounds): 250.

In Pennsylvania: 487.

Life expectancy of an adult mayfly (in days): 1.

Life span of a sidewalk tree in New York City (in years): 7.