Relying on guidance from historical returns is the number one investment mistake made by millionaires, according to a new survey.

The surveyors from deVere Group spoke to 752 investors with more than £1 million investible in the UK and globally.

The top cited mistake (38 percent) was reliance on historical returns, the second (35 percent) was not having sought advice, and the third (21 percent was lack of diversification. A collection of other mistakes and ‘do not knows’ made-up the remaining 6 percent.

deVere chief executive and founder, Nigel Green, said it was encouraging for advice businesses to see r...