Before 1990, the Courts had great difficulty in deciding how the decapitalisation rate should be derived and at what level it should be set when determining the rateable value of a property.
Cyn 1990, roedd y Llysoedd yn cael anhawster mawr wrth benderfynu sut y dylid deillio’r gyfradd ddatgyfalafu ac ar ba lefel y dylid ei phennu wrth benderfynu gwerth ardrethol eiddo.