Within six months after December 3, 1993, the Secretary, in consultation with affected Indian tribes, shall enter into a contract with a non-Federal entity knowledgeable in agricultural management on Federal and private lands to conduct an independent assessment of Indian agricultural land management and practices. Such assessment shall be national in scope and shall include a comparative analysis of Federal investment and management efforts for Indian trust and restricted agricultural lands as compared to federally-owned lands managed by other Federal agencies or instrumentalities and as compared to federally-served private lands.