0
3
6
9
12
15
18
21
24
27
30
33
36
2
5
8
11
14
17
20
23
26
29
32
35
1
4
7
10
13
16
19
22
25
28
31
34
2 to 1
2 to 1
2 to 1
1st 12
2nd 12
3rd 12
1-18
PAIR
IMPAIR
19-36