This is the last monetary aggregate, although it is not widely accepted, as the IMF does not use it. It is the least liquid monetary aggregate, as it includes M3 plus issues of bonds, bills and notes and assets issued by financial institutions that can be considered quasi-money.
M4 = M3+ Bonds, Treasury Bills and Notes.
Related terms
Monetary aggregates | Central Bank | Money | Liquidity | Monetary Base | M1 | M2 | M3 | Money supply