Investment company Alliance Trust said its investment strategy delivered positive absolute returns across all regions last year.Third party assets under management rose to £83m at the end of January 2011 from £12m a year earlier, and have reached £100m since then.The company, which is changing its year-end this year to end-December, saw its net asset value per share rise 16.2% over the year to 439.0p. With full year dividend payments of 8.395p factored in the total return for the year was 18.7%.The fourth quarter dividend in respect of fiscal 2011/11 was 2.2075p. The full year dividend is up 3% on the previous year's pay out of 8.15p and represents the 44th consecutive year of dividend growth.Performance was helped by a share buy-back programme that saw the company buy almost 9.6m of its own shares at a weighted average cost of 335p and a weighted discount to net asset value of 21%.Improvements at Alliance Trust Savings resulted in a reduction in losses by 30% and a 28% increase in revenues to £12.8m. The company said 44% of Alliance Trust Savings' clients are now shareholders in Alliance Trust.Net debt was increased by £127m to £247m. Net gearing stood at 11% at the year end."The near term outlook for stock markets remains clouded by a number of uncertainties, including geo-political risks, rising commodity prices and a global consumer burdened by debt. However, we are optimistic on the prospects for global equities and believe we can exploit the volatility to build long-term positions. We see the best growth prospects in the Emerging Markets and will continue to increase exposure to take advantage of long-term growth opportunities in these regions," said chief executive, Katherine Garrett-Cox. ---jh