public virtual IEnumerable previousperiod(PXAdapter adapter)
{
GLHistoryEnqFilter filter = Filter.Current as GLHistoryEnqFilter;
int?calendarOrganizationID = FinPeriodRepository.GetCalendarOrganizationID(filter.OrganizationID, filter.BranchID, filter.UseMasterCalendar);
FinPeriod prevPeriod = FinPeriodRepository.FindPrevPeriod(calendarOrganizationID, filter.FinPeriodID, looped: true);
filter.FinPeriodID = prevPeriod != null ? prevPeriod.FinPeriodID : null;
return(adapter.Get());
}