When event monitor counting starts - IBM DB2 9.7 for Linux, UNIX, and Windows

Event monitor counting starts at zero, and represents a count since a number of starting points.

Event monitor startup, for database, table space, and tables.
Event monitor startup, for existing connections.
Application connection, for connections made after the monitor was started.
Start of the next transaction (unit of work) or statement after the monitor was started.
Occurrence of a deadlock after the monitor was started.

If you start a statement event monitor after a statement starts, the monitor will start collecting information when the next SQL statement starts. As a result, the event monitor will not return information about statements that the database manager is executing when the monitor was started. This is also true for transaction information.

Event monitor data cannot be reset, except by turning the event monitor off (stopping), and then starting it again.