Following up on the graduation rate debate. I found more reliable, but not perfect, longitudinal data on the number of high school graduates going back to 1880.
The graph shows the degree ratio--the number of high school diplomas conferred divided by the number of 17 year olds. This ratio excludes alternative means of obtaining a diploma, such as the GED, which have been increasing in recent years.
We're interested in 1958 to present. Overall, the trend is flat. If anything, there was an uptick until the mid sixties and then a slow decline back to the baseline until 1980. This corresponds to the big decline in SAT verbal scores, but who knows what this all means.
Anyway, it's more food for thought as to whether graduation rates really correspond to improved academic achievement.