America's high school graduation rate has notably improved, according to figures released last week by the National Center for Education Statistics. The "averaged freshman graduation rate" rose to 78.2 percent of public school students receiving a diploma in 2010, up from 75.5 percent the year before. In 2006, the rate was 73.4 percent, and in 2001, it was 71.7 percent. The new report reflects the best performance in decades by high school students. It is the highest graduation rate since 1970, when the figure hit 78.7 percent. Also improved was the dropout rate, calculated as the proportion of students who drop out in any given year; it fell from 14.6 percent in 1972 to 11 percent in 1992 to 3.4 percent for the class of 2010. Thirty-eight states showed a graduation-rate increase of 1 percentage point or more in the most recent analysis. Overall, 3.1 million students received a diploma in 2010.