In the year to 30 September, the trust's share price and NAV returned 7.5% and 7.2%, respectively, compared to a FTSE All Share index increase of 13.8% in the year.
The underperformance relative to the benchmark means the trust ranks 22nd out of 23 in the UK Equity income trust sector over the last three-year period, only up 11.8% compared to the index's 39.8%.
Over the last year, FGT ranked 14th out of 23, compared with fifth place in 2022. Additionally, the trust's share price has declined since 30 September, falling 2.4%.
Lindsell Train trust NAV dragged down by fund group holding
Chair Simon Hayes described the persistent underperformance as "disappointing", noting this marks the longest such period for the trust since Lindsell Train was appointed as portfolio manager in December 2000.
Hayes noted the recent track record was "concerning" and had been the focus of the board's attention. However, he said the board continues to support manager Nick Train's strategy, noting it has delivered "attractive returns" over the long-term.
"We firmly believe this will continue to deliver strong investment returns to shareholders in the future," he said.
In the results, FGT largely attributed the trust's poor performance to two firms - Diageo and Remy Cointreau - which lost the trust £41.1m and £32.9m over the year, respectively.
Nick Train pledges to 'keep faith' in Lindsell Train holdings as performance lags
Train credited the underperformance to three key factors: Avoidance of commodities and banks, high conviction holdings such as Hargreaves Lansdown and London Stock Exchange Group not performing well and underestimating the significance of technology change.
On the latter, he explained there had been a "huge bull market in companies that are beneficiaries of technology change", and adding that in hindsight, "I wish I had even more exposure to digital winners".
Train said that not owning cyclical and economically sensitive stocks, such as Shell, BP, Glencore, Rio Tinto and HSBC, had contributed to two thirds of the trust's underperformance over the last three years.
"I am not saying I wish I had purchased a basket of commodity and bank shares in late 2020, because that would have run counter to Lindsell Train's, I hope, clearly stated investment approach. But I do wish the portfolio had benefited more from the end-of-Covid-19 bounce," he said.
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The results also noted the trust's ongoing charges had risen from 0.6% last year to 0.61% now, due to the decline in average net assets during the year.
FGT's discount to NAV shrank over the year, down from 5.7% to 4.4%. However, it currently sits at a discount of 6.4%, according to data from the Association of Investment Companies.
To enhance share price performance and narrow its discount, the trust bought back 11,218,558 shares during the year for £97.7m, at an average discount of 4.8%. Since 30 September, it has purchased a further 5,045,317 at a cost of £41.5m, at a 6.4% discount.
The board noted Train had bought 659,604 shares since 1 October 2022 to the date of the report, increasing his stake in the trust to 2.6%, up from 2.2% last year.