CustomerID,CallTime,ToNumber,Duration, Charge
INT, TIMESTAMP, STRING,INT, DOUBLE
1,'2005-01-01 10:00:00','1381231000',180,3.6
2,'2005-01-02 10:57:00','1381231000',80,1.6
3,'2005-01-02 12:57:00','1381000',54,1.08
2,'2005-01-04 13:57:00','1381231000',72,1.44
2,'2005-01-05 10:53:20','1381231000',270,5.4
3,'2005-01-06 10:07:00','45234523',850,17.0
1,'2005-01-07 9:40:00','1381231000',40,0.8
3,'2005-01-08 10:57:00','74621641',80,1.6
1,'2005-01-09 10:57:00','14113634636',80,1.6