EXCP is EXecute Channel Program. This count refers to the number of I/O type signals transferred between the two.( it may refer to count of times the program access the step or it may also refer to count of times the terminal and mainframes communicate.)
CPU% refers to the percentage of CPU used by an active user and it is 0% for the non active users.
REAL refers to the memory used by the user for any kind of activity(job execution...).
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