I have made several excels for computation purpose - progress measurement calculation of a large project, monthly budget sheets, etc.
I can prepare a sheet for you which will be automated. Based on your inputs, Your income would be kinda constant, also some expenditures would be constant for each month. Also you can split your total savings into different heads for your calculations. Will provide a summary sheet wherein you can get your quick data and each months comparison. I already have 2-3 formats ready for this.
Can give you many such options but will need to understand your exact requirement first. So can we connect to discuss about it before you award the project.