A method and apparatus for calculating a cost index in a communication network. In one embodiment, a plurality of first cost factors associated with a first set of network elements is obtained. Subsequently, a plurality of second cost factors associated with a second set of network elements is obtained. A first cost index is then determined based on the plurality of first cost factors associated with the first set of network elements. Similarly, a second cost index is determined based on the plurality of second cost factors associated with the second set of network elements. Afterwards, the first cost index is compared to the second cost index to determine a point in time when a service provider should minimize new investment in the first set of network elements.