Price history from surveys taken in November of even number years are also available.
That is up five percentage points from the survey taken seven years ago.
The list, based on two surveys taken last year, has more than 2,100 sites.
The rankings are based on surveys taken by current students at the school.
She based her estimate on a 1985 survey taken from the 1980 national census.
By contrast, a survey taken in 1973 found an average dropout rate of 19 percent.
But a survey taken now may offer different results.
Teachers worked from about 35 to 46 hours a week, in a survey taken in 1993.
This might help, for instance, in taking accurate surveys of bottom fish.
On the next page, find out about survey Web sites that pay you to take surveys.