There are authorized to be appropriated $25,000,000 for the fiscal year ending June 30, 1972; $65,000,000 for the fiscal year ending June 30, 1973; $100,000,000 for the fiscal year ending June 30, 1974; $160,000,000 for each of the fiscal years ending June 30, 1975 and June 30, 1976; $40,000,000 for the period July 1, 1976, through September 30, 1976; and $160,000,000 for each of the fiscal years ending September 30, 1977, and September 30, 1978, to carry out this section. For the fiscal year ending September 30, 1979, there is authorized to be appropriated (1) $153,000,000 for grants and contracts under paragraphs (3) and (6) of subsection (a) for drug abuse treatment programs, and (2) $24,000,000 for grants and contracts under such subsection for other programs and activities. For grants and contracts under paragraphs (3) and (6) of subsection (a) for drug abuse treatment programs there is authorized to be appropriated $149,000,000 for the fiscal year ending September 30, 1980, and $155,000,000 for the fiscal year ending September 30, 1981; and for grants and contracts under such subsection for other programs and activities there is authorized to be appropriated $20,000,000 for the fiscal year ending September 30, 1980, and $30,000,000 for the fiscal year ending September 30, 1981. Of the funds appropriated under the preceding sentence for the fiscal year ending September 30, 1980, at least 7 percent of the funds shall be obligated for grants and contracts for primary prevention and intervention programs designed to discourage individuals, particularly those in high risk populations, from abusing drugs; and of the funds appropriated under the preceding sentence for the next fiscal year, at least 10 percent of the funds shall be obligated for such grants and contracts. For carrying out the purposes of this section, there are authorized to be appropriated $15,000,000 for the fiscal year ending September 30, 1982. Of the funds appropriated under the preceding sentence, at least 25 per centum of the funds shall be obligated for grants and contracts for primary prevention and intervention programs designed to discourage individuals, particularly individuals in high risk populations, from abusing drugs.