Chapter 19: Analysis of Return on Investment | ROI of Software Process Improvement: Metrics for Project Managers and Software Engineers

16.4 Software Capability Maturity Model

The benefits of using the Software Capability Maturity Model to help produce 10,000 lines of code are $3,023,064. This was obtained by subtracting $1,486,933 in new total life cycle costs from $4,509,997 in old total life cycle costs.

The special, new, or additional costs that are required consist of process, product, preparation, assessment, and inspection costs. The special costs that are necessary to help produce 10,000 lines of code are $56,100, $117,600, $36,800, $30,100, and $70,833, respectively. This totals $311,433 to introduce the Software Capability Maturity Model as a SPI method.

The development cost of $254,400, testing cost of $195,000, and maintenance cost of $966,700 were not included as special costs. The development, testing, and maintenance costs either stayed the same or decreased. Had the development, testing, or maintenance costs increased, the differences or the increases would have been included.

Let's determine the B/CR of the Software Capability Maturity Model to help produce 10,000 lines of code. Divide the benefits of $3,023,064 by the costs of $311,433 for the Software Capability Maturity Model . The B/CR of using the Software Capability Maturity Model to help produce 10,000 lines of code is 10:1.

However, the benefits of the Software Capability Maturity Model must be adjusted, by first removing the costs. That is, the costs of inserting the Software Capability Maturity Model as a SPI method must first be removed from the gross benefits. We will call these the adjusted benefits of the Software Capability Maturity Model . Subtract $311,433 in Software Capability Maturity Model costs from $3,023,064 in gross Software Capability Maturity Model benefits. The result is $2,711,631 in adjusted benefits. Table 23 illustrates the ROI of the Software Capability Maturity Model .

Table 23: ROI of Software Capability Maturity Model
SPI Method	Benefits/Costs
SW-CMM Benefits (Gross)	$3,023,064
SW-CMM Costs	$311 ,433
SW-CMM B/CR	10:1
SW-CMM Benefits (Adjusted)	$2,711,631
ROI	871%

Now we are ready to determine the ROI of the Software Capability Maturity Model to help produce 10,000 lines of code. Divide the adjusted benefits of $2,711,631 by the costs of $311,433 for the Software Capability Maturity Model . Multiply the result by 100%. The ROI of using the Software Capability Maturity Model to help produce 10,000 lines of code is 871%.