Once a world leader, the United States has fallen behind other nations in the educational attainment of its population. Although the percentage of adults age 45 to 54 who hold at least a baccalaureate degree is higher in the United States than in other Organisation for Economic Co-operation and Development (OECD) nations, the United States now ranks below several other nations, including Norway, the Netherlands, Korea, New Zealand, Denmark, and Sweden, in the share of adults age 25 to 34 who hold this credential. While the U.S. invested heavily in the educational attainment of earlier generations, other nations have been investing substantially in their younger populations. Essentially, educational attainment has stalled in the United States, with about 30% of adults in each age cohort holding at least a bachelor's degree. Over this same period, however, educational attainment has been rising dramatically in some other nations. In Korea, for example, 34% of adults age 25 to 34 now hold at least a baccalaureate degree, up from just 17% of adults age 45 to 54.1