Using the 7 grounds for legal abortion, the weight of each grounds (Wi) will be determined based on the percentage (Pi) of countries that allow it. In the weighted index, countries are given a score on a scale of 0-1, where 0 represents countries in which there are no conditions for legal abortion, and 1 represents a country that accepts all criteria for abortion, including on request. The need for a weighted scale is as follows: It would be imprecise, for instance, to suggest that the criterion of saving a woman's life is equivalent to (and thus carries the same weight as) allowing abortion on demand. The more permissive the criterion, the less likely that it is universally accepted. Thus, the scale accounts for the different degrees of acceptance that each criterion represents.