Time zone data is obtained from clients, such as web browsers, which
interact with a server, and used to classify metrics of the clients such
as response times. This classification technique does not require that a
mapping of IP addresses to geographic location is available. Metrics from
the clients are communicated from the server to a manager, which
aggregates the metrics for each time zone. The manager can automatically
associate geographic descriptors, such as names of cities, with the
metrics in a report such as in a user interface display. If a partial
mapping of IP address to location is available, the report can aggregate
metrics which are grouped by IP address separately from metrics which are
not grouped by IP address. The user interface display can be
automatically populated with selectable nodes which allow a user to
selectively view the metrics.