Not vlookup, formula in excel

[rgill84]

Hi All,
I need help creating a formula in excel. I have attached my sample worksheet. I have the data in column A-C. I need to in-put formula that will sum up transactions by looking up the project number and display them in each month.
I don't want to do vlookup. I'm hoping to do it using formula. Number with 0 in the front is must to keep it that way.
Also, if there #N/A for no value found then have that column left blank.