agree strongly
agree
neither agree nor disagree
disagree
disagree strongly
primary incomplete
primary completed
secondary incomplete
secondary completed
tertiary incomplete
tertiary competed
16-24
25-34
35-44
45-54
55-64
65--
male
female
A++
A+
A
A-
A--
B++
B+
B
B-
B--
C++
C+
C
C-
C--
D++
D+
D
D-
D--
-p
p
-s
s
-t
t