Does it pay to stay in school? The report Trends in Higher Education (The College Board, 2010) looked at the median hourly wage gain per additional year of schooling in 2007. The report states that workers with a high school diploma had a median hourly wage that was 10% higher than those who had only completed 11 years of school. Workers who had completed 1 year of college (13 years of education) had a median hourly wage that was 11% higher than that of the workers who had completed only 12 years of school. The gain in median hourly wage for each additional year of school is shown in the accompanying table. The entry for 15 years of schooling has been intentionally omitted from the table.

a. Use the given data to predict the median hourly wage gain for the fifteenth year of schooling.
b. The actual wage gain for fifteenth year of schooling was 14%. How close was the predicted wage gain percent from Part (a) to the actual value?

2007 Median Hourly Wage Galn for the Additional Year (percent) 10 Years of Schooling 12 13 14 16 17 18 13 16 18 19