From the report abstract:
ERP systems can be major investments requiring a substantial effort in implementation. Yet many organizations do not realize that the total cost of ownership of an ERP system is composed largely of ongoing support. In this report, we analyze ERP support staffing levels by size of the installation, the scope of functionality implemented, class of software vendor (Oracle and SAP vs. all others), the extent of system modification, the number of ERP versions and instances in production, and the age of the system. In addition, we analyze the allocation of ERP support staff to specific job functions. Based on these statistics, we conclude with recommendations for optimizing ERP staffing levels to better manage costs and improve user satisfaction.The full report, ERP Support Staffing Ratios, is available for purchase. There is also a free executive summary if you follow the link.