For example, paddy rice, if it is irrigated, can yield a maximum of 5.5 tons per hectares in the sampled fields, but without irrigation the yield rarely goes above 4 tons per hectares. A recently released report by IFPRI (Svendsen, Ewing, and Msangi 2009) finds that irrigated yields in Africa are typically 1.5 to 3 times of those of rainfed yields. It should be noted that water footprint measurements do not necessarily relate to the opportunity cost of water, which can lead to blatant misinterpretations.