obsid   target                  start time      int time    inst    ccd     grat    drop rate(%)
-----------------------------------------------------------------------------------------------------------
3696	CAS_A[I3,-120,-     	76:04481.032		 2.4	ACIS-I	I6		NONE	4.5
3697	CAS_A[S3,-120,-     	76:08563.219		 2.1	ACIS-S	S6		NONE	7.5
3703	CAS_A[I3,-120,-     	292:32595.477		 2.1	ACIS-I	I6		NONE	4.4
3704	CAS_A[S3,-120,-     	292:36382.075		 2.1	ACIS-S	S6		NONE	7.5