You're given the following table (along with the Python code to generate it) showing student information:

# Python code to generate example dataframe
import pandas as pd
import numpy as np
raw_data = {'age': [20, 19, 22, 21, 21, 22, 23, 23], 
        'major': ['Engineering', 'Business', 'Engineering', 'Engineering', 'Business', 'Business', 'Engineering', 'Engineering'], 
        'grade': [88, 95, 92, 70, 68, 92, 75, 85], 
        'perc_attendance': [88,95,95,92,78,87,91,np.nan],        ...