assigned value 

https://doi.org/10.1351/goldbook.08057
Value attributed to a particular property of an item and that serves as an agreed reference for comparison.
Notes:
  1. The value may be a reference quantity value or a value of a nominal property.
  2. Options for establishing an assigned value for some types of proficiency testing schemes are detailed in ISO/IEC 17043 and ISO 13528.
See also: property value assignment
Source:
PAC, 2021, 93, 997. 'Metrological and quality concepts in analytical chemistry (IUPAC Recommendations 2021)' on page 1020 (https://doi.org/10.1515/pac-2019-0819)