Wright Williams & Kelly
TECHNICAL ALERT #5
1) WWK has identified an error in the Cost of Ownership Calculation reports for scheduled maintenance time per system. This error only occurs if the number of systems being analyzed is greater than one and the primary or secondary wafer (unit) based maintenance inputs are utilized. All other calculation scenarios are correct.
If the above conditions are met, then the calculated scheduled maintenance per system will actually be the total scheduled maintenance for all systems. This will result in a lower number of available hours and, therefore, a higher cost of ownership result.
2) WWK has identified an error in Microsoft's implementation of declining balance depreciation methods. This error only occurs if "db" is selected as the depreciation method. All other depreciation methods are correct.
If declining balance is used, the depreciation calculated in the 5 Year Tables will be underestimated (8% for double declining balance over 5 years). The Life Summary Tables are correct.
Both issues will be corrected in TWO COOL® v2.1.1.