Calculating a total

Hi all,

I have a dataset whereby I add revenue numbers into a currency field for each order. We may have 100 orders in a month and each order will have a revenue figure in it. 

I now want to create a view/web part/page that summarises and displays this data on a monthly basis and adds a total (sum) or all the revenue for all opportunities. See below:

Does anyone have any guidance or could point me towards a tutorial of how to do this?

Thank you!!!

Andrew