How do you write a Server Software Return on Investment Calculator?

Server Software Return Investment Calculator Year Year Year Year Year Total Server Software Cost Hardware Costs Consulting Services Staffing Costs Building Costs Software Upgrades Cost Total Costs Reduced Per Seat License Costs Reduced Staffing Costs Increased Performance Costs Reduced Support Costs Benefit Benefit Benefit Total Benefits Net Savings Ratio DIV DIV DIV DIV DIV DIV ROI DIV DIV DIV DIV DIV DIV