As the table shows, the most heartening and robust statistic to emerge from these surveys was an improvement in African-American scores over the span covered by the two surveys.

• 如右表所示，在这些研究中最令人振奋与欣慰的统计是在这两次研究所涵盖的时间里，非裔美国人的分数有明显的改善，其他的改变则较不稳定。