4/2	4/9	4/16	4/23
S1	S1	S2	B
S1	S1	P	S2
S1	S1	S2	B
S1	S1	S2	P
S1	S1	S2	B

5/7	5/14	5/21	5/28
S1	S1	S3	P
S1	S1	S3	B
S1	S1	S3	P
S1	S1	S3	B
S1	S1	S3	P