Job
Each Job has a record in this table.
Cost
Each Cost center has a record in this table.
JobCost
Each Job by Cost center combination has a record in this table to specify the Estimate values and summarize Actual values.
Project
Each Project has a record in this table.
Each Job must be assigned to a Project.
CostGroup
Each Cost Group has a record in this table.
Each Cost center must be assigned to a Cost Group.