You are analyzing the data of retention rates of MBA students at a business school. According to the school, 31 students graduate each year, but only spend 3 years with their first employer. (On average). The last 5 years the data shows that the number of MBA students staying with their first employer has been 180, 92, 150, 103, 125.

Based on this data, what can be concluded about the average number of years these MBA students spend with their first employer?