How TO RECORD live DATA FROM A WEB

Hi,

I have a developed an auto refreshing excel sheet which collects data from a website. I want to if there is a way i could keep some of the calculated results based on this data in a tab. It should remain uncahnged when the data refreshes . eg below

The excel fetched the following numbers from a website

in tab 1 (230) and in tab2 (330 ) now i have made  tab 3  to record the total of both (560) sat 1.00 pm

after 5 mins when data refreshes in tab 1 (100 ) and in tab 2 (200)  now i want to record the total of 300 meanwhile keeping the 560 recorded at 1.00 PM

the data 

Tab 1   Tab 2   Tab3 (Sum)       Tab4 (Time)

230    330       560                  1:00 pm

100    200       300                  1:05 pm