Summarize cost info by both contract and month

I've got a daily cost tracker spreadsheet which vertically lists various items in one column with a contract reference in another column (multiple items per contract). Then, there is a column for each day where daily costs, if any, are captured. I'm trying to find a way to summarize the data by both contract and month. A screen capture of part of the cost tracker shown below: 

Can anyone advise how, using formulas and/or pivot tables etc, I can generate a summary report by contract and by month?