I searched the forum and found some help with a personal expense tracking spreadsheet I'm creating for myself, but I need to add a second condition to the SumIf command. Is this possible or is there another way to accomplish this?

My spreadsheet is a very basic expense log with 4 columns: A=Date, B=Amount, C=Category (Gas, Food, Tuition, etc.) & D=Type (Cash, Check, VISA, etc.). To summarize the expenses, I am trying to create a table with the categories (going down) and the months (going across). To populate the first cell in the table, I need to sum all amounts spent on Gas in January. The formula =SUMIF(C:C,"Gas",B:B) allows me to sum all amounts spent on gas, but how can I add the second condition (spent in January) in the same cell formula? Once I figure this out, I can place similar formulas in the remaining table cells.

Thanks for your time!