Automated Data Update

Hello all,

I call upon you once again!

I have two query’s regarding a spreadsheet I have made.

Firstly I want to have a ‘Current Mean’ which will display the current average from a data set not displayed, so obviously whenever new data is added the mean needs to update itself without having to manually equaled to the next value.

Also I have a graph which displays a running total of data which a mean line on it, new data is entered once a week into the data set but I have to manually update the source data on the graph itself otherwise it displays all the empty values for the year. I want this to be automated so any new data added just updates the graph. Example of the data layout is below.

Date..........Totals..........Mean

01/01/10..........4..........4
08/01/10..........6..........5
15/01/10..........8..........6
22/01/10..........10..........7
29/01/10
05/02/10

Thanks

Anyone help me with this?