[ESMA 70-1861941480-56 MiFIR data reporting Q&A, Q&A 22.1]

The population of field 17 should be in line with the characteristics defined in the prospectus, as indicated in its own prospectus or admission document. In case the instrument was issued in units, field 17 should be populated with the nominal value per unit. If the instrument was issued in nominal amount (e.g. instrument priced in percentages), then field 17 should be populated with the minimum traded value (i.e. the minimum specified denominations, in case such denominations are available, otherwise the lowest specificied multiples).