Cacti - http://www.cacti.net/

Exported Graphs

Graph - Richmond WiFi - Clients
Hourly (1 Minute Average)

Daily (5 minute snapshot)

Daily (5 Minute Average)

Weekly (30 Minute Average)

Weekly (30 minute snapshot)

Monthly (2 hour snapshot)

Monthly (2 Hour Average)

Yearly (1 Day Average)

Yearly (1 day snapshot)