; and (ii) provides notification and the rationale for the determination to the congressional defense committees before awarding the contract. (4) Measurement of reliability and maintainability In carrying out paragraphs (2) and (3), the program manager shall base determinations of a contractor’s performance on reliability and maintainability data collected during developmental testing, operational testing, or the operation of a fielded weapon system as measured and validated by the military department concerned on a date chosen by the program manager and specified in the contract. . (2) Clerical amendment The table of sections at the beginning of subchapter I of such chapter is amended by adding at the end the following new item: 2442. Sustainment factors in weapon system design. . (b) Deadline for guidance The Secretary of Defense shall revise guidance as required by subsections (b) and (c)(3) of section 2442 of title 10, United States Code, as added by subsection (a), not later than 180 days after the date of the enactment of this Act. (c) Effective date for certain provisions Subsections (c) and (d) of section 2442 of title 10, United States Code, as added by subsection (a), shall apply with respect to any weapon system development and production contract for which the contract solicitation is issued on or after the date occurring one year after the date of the enactment of this Act. (d) Investment program authorized (1) In general The Secretary of Defense shall establish an investment program for funding engineering changes to the design of a weapon system in the development or production phase of an acquisition program to improve reliability or maintainability of the weapon system and reduce projected operating and support costs. The program may be funded from the Defense Modernization Account authorized in section 2216 of title 10, United States Code. A program manager may apply for available funds by presenting a business case analysis of the anticipated return on investment of such funds. (2) Guidance