; and (B) adjusted for family size. (9) Secretary The term Secretary means the Secretary of Health and Human Services. (10) State The term State means a State, the Commonwealth of Puerto Rico, the District of Columbia, Guam, American Samoa, the Virgin Islands of the United States, and the Commonwealth of the Northern Mariana Islands. The term includes the Republic of Palau, except during any period for which a Compact of Free Association is in effect, contains provisions for early childhood education or development, and prohibits the assistance provided under this subchapter. 638. Authorization of appropriations There is authorized to be appropriated to carry out this subchapter $8,598,000,000 for each of fiscal years 2017 through 2021. 639. Block grants to eligible states and indian tribes (a) In general Notwithstanding any other provision of this subchapter, beginning on October 1 of the first fiscal year following the date of enactment of the Head Start Improvement Act of 2017, from the amounts appropriated to carry out this subchapter under section 638 for a fiscal year, the Secretary shall award grants to eligible States and Indian tribes from allotments made under subsection (b) in accordance with this section. (b) Allotments (1) Formula The Secretary shall allot the amount appropriated under section 638 for a fiscal year among the eligible States and Indian tribes in proportion to the number of children, age 5 and younger, who are from families with incomes below 100 percent of the poverty line for the most recent fiscal year for which satisfactory data are available and who are in an eligible State or Indian tribe, compared to the number of such children for that fiscal year who are in all eligible States or Indian tribes. (2) Calculation For purposes of counting the number of children who are in an eligible State under paragraph (1), the children who are counted in an eligible Indian tribe in that State shall be excluded. (c) Application To be eligible to receive a grant under this section, a State or