Monetary management was increasingly entrusted to administrative controls on credit, namely the ceiling on the growth in bank lending (introduced in 1973) and the requirement that banks invest a part of their portfolios in long-term fixed-income securities. Initially designed for allocative purposes and to support private investment, these instruments were almost immediately employed for macroeconomic purposes and to facilitate the financing of the Treasury.
Effective in rapidly curbing aggregate demand, they continued to be used until the end of the 1980s in spite of their allocative cost and the fact that they soon came to be circumvented. Treasury bills were the main instrument for financing the Treasury.