A regnal year dating system had an accession year (often referred to as Year 0 by historians) for the remainder of the calendar year during which they acceded the throne and became king.
Usoro mmekorita nke afọ nke afọ nwere afọ nnabata (nke ndị ọkọ akụkọ ihe mere na-akpọ ya dị ka afọ 0) maka oge fọdụụrụ afọ kalenda mbụ oge ha wee were ocheeze wee bụrụ eze.