The reference quarter is the more recent of the two quarters of [glossary:CPI:622] or [glossary::668] data used in indexing a payment rate, limit or threshold. The reference quarter CPI or PBLCI figure is compared to the [glossary:base quater:319] CPI or PBLCI figure to determine the indexation factor to be applied. The reference quarter is defined in the legislation and varies according to the amount being indexed.