The Soap Company uses job costing and applies overhead using a normal costing system using direct labour hours as the allocation base. This period's estimated overhead cost is $400,000, estimated direct labour cost is $500,000 and estimated direct labour hours are 25,000 . This period's actual overhead cost was $420,000, actual direct labour cost was $390,000, and actual direct labour hours were 20,000 . What is the overhead allocation rate