Many factors for the decline in interest rates, but past few decades 80's onwards I would factor in: 1) The recessions of the 70's and subsequent bumps showed

Many factors for the decline in interest rates, but past few decades 80's onwards I would factor in: 1) The recessions of the 70's and subsequent bumps showed that high interest rates in such times hurt the populas deeply. 2) Lower interest rates enable economic stimulus 3) QE can be used to keep interest rates down and stimulate the money, so it may stimulate the economy. The future - we are seeing things like negative interest rates come into play. Personal view is the whole shift to silly low interest rates has driven people away from responsible money management and from a save for a rainy day towards have now pay tomorrow. The real downside is that low interest rates discourage savings and those that do save are now not so well off.