§ 51. Interchange of appropriations or items therein. No appropriation shall be increased or decreased by transfer or otherwise except as provided for in this section or section fifty-three, sixty-six-f, seventy-two or ninety-three of this chapter, or article eight of the education law. Whenever an appropriation is made from a fund to a department or agency and is accompanied by a schedule showing the programs or purposes for which such appropriation may be expended, the amount appropriated for any item or items within any program or purpose for such department or agency may be increased or decreased by interchange with amounts appropriated from such fund for any other item or items within the same program or purpose, or with other items appropriated from such fund not in the same program or purpose but which are contained in the state comptroller's classification of items as last promulgated, with the approval of the director of the budget, who shall file such approval with the office of the state comptroller and copies thereof with the senate finance committee and the assembly ways and means committee. The amounts appropriated to a department or agency from a particular fund in a fiscal year for the programs or purposes of such department or agency may be interchanged among such programs or purposes under the same conditions as heretofore described except that the total amount appropriated for any program or purpose may not be increased or decreased by more than the aggregate of five per cent of the first five million dollars, four percent of the second five million dollars and three per cent of amounts in excess of ten million dollars of an appropriation for a program or purpose. The allocation of lump sum appropriations from a fund made to a department or agency for later distribution to programs or purposes or to the units of the state university to the allocation of lump sum appropriations made to all state departments and agencies for later allocation for specific programs or purposes shall not be deemed to be part of such total increase or decrease.