how can subtraction price from a list if the data is Null

[#1]

Hi all,

I have a table and text object.

The table have data and prices culomn and want when data is null the text object give me the total of prices just who have data recorded

for example:

Data Price

01/2010 $ 30

$ 1000

02/2010 $ 50

total = $80

thanks

[#2]

something like this:

sum(if(not isnull(Data), Data))

[#3]

meant this:

sum(if(not isnull(Data), Price))

[#4]

Hi Daniel Viklinder thanks for your answer .. but the result gave me the sum of who haven't Data ... what i need it sum ofwho have a data .... thanks