SharePoint 2013 is out but i still get the queries regarding the usage reporting capability of SP 2010.
Some pointers below.
- The data displayed by SharePoint Web Analytics is pulled from "WSS_Logging" database. It aggregates all of the raw logging data accumulated in the text files under the 14 hive and imports it into logging database.
- Web Analytics Service Retention Policy
To persist the usage data in WSS_Logging for longer time you can change the retention policy
by changing the settings in central administration
Central Administration - > Application Management - > Manage Servcie Application
- >Select Web Analytics Service ->Click "Properties" in ribbon ->Change Data Retention
Period
up to 25 months.
- The data import from Logs files to Database is performed by Timer Job " Microsoft SharePoint Foundation Usage Data Import"
You can set the frequency of timer job depending on load on your server.
- More Information on Logging DB can be found at :
http://technet.microsoft.com/en-us/library/hh769360(v=office.14)