When a star fund manager like Thomas Moore sees his closely-watched performance rating fall through the floor, as it did in June, it can’t be easy.

The Standard Life Investments manager topped The Herald’s Citywire league table for months on end last year, and his £1.1billion equity income fund was regularly lauded by commentators and analysts as being among the top handful in its class and in the UK market.

But midway through this year, and a week after the EU referendum, the fund was the worst performer in its peer group in 2016 and Mr Moore was languishing in 98th place in Citywire’s equity income manager table.

Colleagues at Standard Life Investments have also endured a torrid spell, with only one SLI fund in four beating its benchmark over one year, compared with 17 out of 20 over three years, Standard Life revealed this week.

Mr Moore is upbeat. “We have had a poor June but a very good July. The near-term impact of the vote has created a lot of noise and as stockpickers we have to be aware of why it happens. We spend the bulk of our time picking stocks, that is our greatest strength, we have a team of 12 people and a process called ‘focus on change’ which works – the stats show our stock level analysis works.”

He goes on: “You do have to keep reminding yourself. From time to time you think ‘this is hard going’, and it is frustrating, because we are confident that our process will produce some attractive returns for investors.”

He is bullish on the economy too. “The service data are pretty bleak but these are sentiment surveys. People had been told this was going to result in an immediate recession.

“We spend most of our time meeting companies and the commentary we are getting is life goes on and actual activity levels have been little altered. It doesn’t feel anything like a recession.”

The Kentish boy was always going to manage money. “I started investing when I was 13, when the water privatisation happened. I remember saying to my mum I had built up enough money to put a couple of hundred pounds into it, and thinking was it all about putting your money into a building society or National Savings, or was there a more creative way of saving.

“I worked on that from an early age and made a lot of mistakes along the way, but that is quite helpful over time, you have to learn the hard way.”

After economics and politics at Exeter, a year in Aix en Provence confirmed him as a Europhile and French speaker, as did marrying his Norwegian wife Kathrine which gave him a third language – and now three children aged two to nine.

His first job was at Schroders. “I had a passion for investing and wanted to learn from some of the great investors at Schroders as I have at Standard Life Investments, you are constantly learning and you need to be humble enough and see there are always things you can learn and do better.”

His ‘unconstrained’ equity income fund means the 40-year-old has the relatively rare privilege in fund management of an entirely free hand to invest where he will, with no regard to an index. “We have a head start on other investors,” he insists. “We are not starting with a rather contrived prop called the index and working backwards, we are starting with our research-led conclusions on what makes a successful investment.”

But the fund is hardly esoteric. It has 45per cent in the FTSE-100, a third in financials, its top 10 holdings account for 31per cent of the fund, and are led by big names such as BT, Sage Group, Vodafone, Aviva, Imperial Tobacco, Rio Tinto and L & G.

As an analyst Mr Moore’s speciality was the banking sector, and despite his scepticism about many banks he says Lloyds is in good shape. “If there were a recession now Lloyds would sail through.”

His fund is known for shunning many of the ‘mega-cap’ stocks which form the staple of most income-seeking portfolios and funds, helping to explain why it fell from grace in its sector as investors became more risk-averse.

Mr Moore produces a spreadsheet showing how the major oil and gas, basic materials, banking, and healthcare companies dominate the FTSE-100. “You quite quickly get to around half the index coming from a handful of stocks.But if you look carefully at the balance sheets of these companies and earnings trends, there is reason to be cautious.” He cites the latest results from BP, Shell and HSBC. “They are 15 per cent of the UK market and by default 15 per cent of the typical saver’s UK equity weighting in a traditional fund or a passive fund.

“There are risks. As the government pushes more and more of us into reliance upon equity markets, people need to be aware of the risks of being too highly weighted in stocks with these sorts of risk – the high yield is there but the sustainability is in question.”

His fund also steers clear of what he calls “the low-yielding stocks perceived as highly reliable” in sectors such as utilities and food production which appear to offer bond-like returns - but are so popular that they look expensive.

Instead, his team focuses on the companies that will continue to grow their dividends even in a tougher macro-environment, "which may be overlooked".