• At billing time, when "real" consumption cannot be computed due to the lack of a meter read, the system estimates how much the customer used assuming the following conditions are true:

◦ The service agreement allows estimation.

◦ The rate schedule allows estimation.

◦ The bill cycle schedule (if one is being used) allows estimation.

◦ The register is not a peak register (this is an artificial constraint, but most organizations do not estimate peak consumption). Note that the base product estimation algorithms may attempt to estimate peak registers.

◦ The register is subtractive. This is because only subtractive registers are self-correcting. For example, assume we estimate a reading of 100 and the next real read is 102, the customer will only be charged for 2 units. But consider what would happen if we estimated a consumptive register, the consumption associated with the next real read will be billed in its entirety.

• When a meter read is added, the system verifies that the resultant consumption is congruous with historical consumption trends (i.e., high / low checks are performed).