Final answer:
Young Americans are increasingly concerned about specific issues and tend to align themselves as Independents. The youth vote has been on the rise in recent years.
Step-by-step explanation:
According to the information provided, it is difficult to determine the exact percentage of young voters who give more weight to economic policies over social issues. However, the data suggests that young Americans are increasingly concerned about specific issues, such as same-sex marriage, and tend to align themselves as Independents rather than identify with a particular political party. It is also mentioned that the youth vote has been on the rise, with a higher turnout among 18 to 24-year-olds in recent years. Although specific percentages are not mentioned, these trends indicate that a significant portion of young voters prioritize social issues.