LONDON -- Alliance Trust (LSE:ATST), a self-managed investment firm, has just had its best first-quarter performance in 15 years. Shares are up 1.7% late in London trading.

Alliance announced today that the shareholder return for the quarter ending in March was 15.2%, while its net asset value increased 13.6%. These results, it says, owed to strong performance from global equities.

The company said that over the quarter, the best-performing sectors were health care, with a 22.3% increase; consumer staples, up 19.5%; and consumer discretionary, lifting 16.4%. Alliance said the weakening of the sterling had a positive impact on its portfolio.

Alliance said its portfolio activity in the quarter was a reflection of management's decision to increase exposure to equities. There have been a number of significant changes to the equity portfolio over the first quarter: Notable new additions (140 million pounds of the 220 million pounds initiated last quarter) include positions in Walt Disney, Zurich Insurance, Barclays, and Infineon Technology.

The first quarter of 2013 included a key milestone for Alliance Trust Investments, the firm's fund arm opened just four years ago. By the end of the quarter, assets under management exceeded 2 billion pounds for the first time. Alliance Trust Investments now has a range of 13 funds.

Meanwhile, at Alliance Trust Savings, there has been a 54% increase in the number of accounts opened in Q1 2013 compared with the prior year. AUM for the group has increased 15% to 4.6 billion pounds. Alliance said total inflow of new business from advisors in the first quarter of 2013 is greater than was seen in the whole of 2012 as advisors increasingly seek a cost-effective platform for their clients in light of the Retail Distribution Review.

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