This debt graph covers 1994 to 2009. What trend does the graph demonstrate?

• A. Debt remained flat.
• B. Debt decreased.
• C. Tuition for higher education has risen steadily since 1994.
• D. Enrollment has declined.

Answer: (C)

When you read a time-series graph, the main idea is to look at how the value changes from year to year. A steady upward path means the quantity is increasing over time. In this case, from 1994 to 2009 the debt shown keeps rising year after year, which aligns with tuition costs climbing during that same period. So the trend indicated by the graph is that tuition for higher education has risen steadily since 1994, and students are accumulating more debt as tuition goes up.

If the debt had stayed the same, you’d see a flat line. If it had dropped, you’d see a downward slope. The option about enrollment declining would refer to the number of students, not the amount of debt, which isn’t what the graph is illustrating.