It is not an event and neither is it a journey with a fixed end point.

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But as raising interest rates to protect the currency means slowing the economy, a government might at some point decide that the pain of maintaining the fixed exchange rate is not worthwhile.

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And the goal is not time-bound because it has no starting point, no ending point, and no fixed duration.

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That matters not least because, as Morgan Stanley's own analysts point out, the bigger you are in fixed income, the less volatile your returns.

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The timing of general elections is not fixed in the UK. We have taken the five-year time limit imposed on governments as the point at which to judge whether or not a pledge has been met.

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