A standards-based test is an assessment based on the outcome-based education or performance-based education philosophy. Assessment is a key part of the standards reform movement. The first part is to set new, higher standards to be expected of every student. Then the curriculum must be aligned to the new standards. Finally, the student must be assessed if they meet these standards of what every student "must know and be able to do". In the United States, a high school diploma which is given on passing a high school graduation examination or Certificate of Initial Mastery is awarded only when these standards are achieved. It is fully expected that every child will become proficient in all areas of academic skills by the end of a period, typically 10 years in the United States, but sometimes longer, after the passing of education reform bill by a state legislature. The United States federal government, under No Child Left Behind can further require that all schools must demonstrate improvement among all students, even if they are already all over proficient.