I believe that these changes constitute a considerable departure from previous practice both in terms of “quantity” (based on the size of the Bank’s Asset Purchase Program) and “quality” (based on the maturity length).
The second characteristic of QQE is an increase in the purchase of two risk assets – exchange-traded funds (ETFs) and Japan real estate investment trusts (J-REITs) – since  BIS central bankers’ speeches  1  there is some room for further lowering of the levels of risk premia (that is, the expected excess returns demanded by investors relative to safe assets) and it is thought that the purchase of the two risk assets will have a large economic impact.