The FASB and IASB (2005, p. 12) state:

The long-standing unresolved controversy about which measurement attribute to adopt—particularly between historical-price and currentprice measures—and the unresolved puzzle of unit of account are likely to make measurement one of the most challenging parts of this project.

Provide an explanation of why measurement will be one of the most ‘challenging’ components of the conceptual framework being developed by the IASB.