There can be many reasons for mapping to other codes and classifications:
Analysing spending is only useful if it achieves something. For instance, knowing what has been spent overall on stationery per year is interesting but cannot be used for anything except comparison, even then, only if everyone agrees what is stationery (i.e. is toner stationery?) and the classification has been applied correctly by everyone. If saving money is an objective, classifying alone will not achieve anything. Adding a CPV Code to provide the automatic translation is very useful.
Please note that the mappings are best fit (1 to 1 mapping). For full mappings please contact Coding International Ltd (CIL) for a quote.
Latest mappings are to version C14.1 of ProClass