$ sudo apt-get remove ifstat 

Uninstall ifstat including dependent package

If you would like to remove ifstat and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove ifstat 

Use Purging ifstat

If you use with purge options to ifstat package all the configuration and dependent packages will be removed.

$ sudo apt-get purge ifstat 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove ifstat 

See Also,