I am trying to tag our fiscal period of 52 weeks with FiscalPeriodDuration, but P52W is not recognized as a period duration. Is there a nuance? I found reference to this exact question in another posting, but it is no longer active. The definition of the concept says "Duration of a fiscal period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter." Although, arguably, the 'PnYnMnDTnHnMnS' does not include a W. Thanks!