The education level of Americans has increased throughout the 20th century. The following U.S Census data show the level of education attained by American adults over the age of 25 years at several points in time.
a. What is the direction of the relationship between each year and level of education?
b. Use percentage differences to describe the relationship. Why don't the percentages add to 100% by year? Is there a problem in analyzing the table?
c. Do these data support the idea that Americans were getting more education in 2006 than in the 1980s or 1990s?
| Education level |
|
| Year |
Highschool Graduate or More (%) |
College Graduate or more (%) |
| 1980 |
66.5 |
16.2 |
| 1990 |
77.6 |
21.3 |
| 1995 |
81.7 |
23.0 |
| 2000 |
84.1 |
25.6 |
| 2006 |
85.5 |
28.0 |