The PeriodMonthly dimension
Similar to actualitymonthly dimension, periodmonthly
is a separate dimension and is aggregated from months into quarters
and then into years. The periodmonthly dimension's year and quarter
levels are not explicitly present in the source. The period hierarchy is
not meant for aggregation; its purpose is to support relative period
logic and to support relative periods in the year following the
financial year, and not the calendar year.