For several years now, investment consultants have been telling the pension funds they advise to consider proofing their investment portfolios against future volatility. With equity markets enjoying a strong upward run – the MSCI World is up 19% in the past two years – it has been a tough sell.

But some large pension funds have gone down this route, wary that bears follow bulls, eventually. The most recent to prepare itself is the £6.6 billion fund for Royal Mail, the postal group, which has hedged the future value of its equity portfolio through a £700 million options strategy implemented over the past month with advice from asset manager River & Mercantile.