01
Minimum fields
Any future observation must record product specification, geography, market level, currency, unit, observation time, publication time, source and whether the value is assessed, transacted, offered or modelled.
02
No silent substitutions
A U.S. benchmark may be a useful reference, but it cannot be relabelled Canadian. A futures contract cannot be presented as a cash plant bid. A retail fuel price cannot stand in for an ethanol wholesale value.
03
Revisions
Corrected source data should be versioned. Method changes should be explained before a historical series is recomputed.