[GRASSLIST:9307] Extracting and sum values in a tab

[Luca Casagrande]

Hi guys

I have got an area vector layer that describes the extension of different 
cities and also the region in where them are; the table associated is 
something like this:

REGION		CITY		EXTENSION	
    A			test1			100000
    A			test2			5000
    B			........			20000
    C                 ........			300000

I'd like to create a surface layer that describes the extensionof each region 
and with a tab like this one:

REGION			TOTAL POPULATION
	A				Sum of all
	B				Sum of all
	C				Sum of all

Can this be done?

Thx
Luca