The statutory language of this amendment is clear that admission of the workers is discretionary. not mandatory. This amendment explicitly sets forth factors that the Attorney General must consider in deciding whether to admit any workers. including the availability of domestic agricultural labor. the historical employment needs of agricultural labor. and the recruitment efforts undertaken by the Secretary of Labor to seek out available domestic workers. It the Attorney General determines that workers are needed. he would then establish a numerical limitation on the number of visas to be issued on a monthly basis for each of the 10 regions established throughout the United States. Only if the Attorney General determined that extraordinary and unusual circumstances have resulted in a significant change in a growers need for workers or in the availability of domestic workers who are able. could the numerical limitation of workers be increased. This increase would be limited to an amount not to exceed 20 percent of the total number authorized for admission into all regions.