blank cells with formulas

I created a spreadsheet in which I have extended formulas to blank cells so that when I input data daily it will add/subtract as necessary, but how do I get the cells to remain empty until I fill them, such as in a check register. It has the formula there, but the next line doesnt calculate until you input the data. I have attached the sheet, and I want the cells from April 5th down to be blank, like a check register, but they are filling in info already.