The statement said this was in order to focus on preserving risk and maintain its risk target, which is two-thirds of the volatility of the MSCI World Index.
Mike Webb, chief executive of Rathbone, said: “We must protect the real value of wealth. In a world of financial repression and negative real yields from fixed income securities, our research shows that we would have to take significantly more equity-like risk for every unit of return.
“This is not the reason why our investors have bought the fund and it is our responsibility to preserve their risk objectives.”
Adrian Lowcock, senior investment manager for Bristol-based Hargreaves Lansdown, said: “It all depends on what is changing and how the fund is structured. This fund was set up to target a specific risk not a specific return, and has presumably been sold on that basis.
“It is like a bank telling you it has changed the interest on your account. In this instance you are paying the fund managers to manage risk so they are just doing their job. The important action to take is clear communication to clients and advisers on what the new expected returns will be.
“This does highlight one of the issues with risk-targeted funds, which Rathbone has acknowledged; its priority is to manage risk not returns. Investors and advisers can consider alternative investments and should be relatively easy to switch from one fund to another if they are not happy with the new returns they anticipate.”