The Office shall allocate 20 per centum of the total amount available for grants under this chapter in such manner as will most nearly provide an equitable distribution of the grants among States and between State and local governments, taking into consideration such factors as the size of the population, number of employees affected, the urgency of the programs or projects, the need for funds to carry out the purposes of this chapter, and the potential of the governmental jurisdictions concerned to use the funds most effectively.