WHARF Holdings saw net profit after tax and minority interests reach $2.05 billion in the 12 months ending December 31, compared with $1.28 billion for the nine months ending December 31, 1991. The company has changed its accounting period from March 31 to December 31 with effect from December 31, 1991. Executive director John Hung said the increase in profit made on an annualised basis amounted to 20 per cent. In a company statement chairman Peter Woo Kwong-ching said: ''While pursuing strategic investments in China, Wharf remains a group which continues to rely extensively and fundamentally on core investments with a long-term presence in Hongkong.'' Mr Hung, however, indicated that a soft office rental market had led the company to remain open to potential offers for Times Square Tower A. ''We do not have plans to put it up for sale. Of course if someone did come along with an interesting offer then we would have to consider it seriously,'' said Mr Hung in a briefing on the financial results. Group earnings per share last year were 97.8 cents, compared with 61.2 cents in the nine-month period in 1991. Dividend per share was 65 cents, compared with 56.5 cents in the nine-month period in 1991. The consolidated net asset value of the company was said to be 21.32 cents a share, up 30 per cent on the same date a year earlier. Under an accounting change bringing investment property disposals out of extraordinaries and into turnover along with the operating profit, the operating profit figure was boosted by $211.3 million. ''Had the above change not taken place, the growth in net profit would have been in excess of 14 per cent over the previous nine-month period, again on annualised basis,'' said the company. Group turnover over the period was $4.39 billion. Mr Woo said: ''Wharf is essentially an asset growth driven group with a focus in Hongkong and in the last several years, we have been adding incrementally to our asset base with projects or acquisitions in Hongkong, in Singapore, the United States and beginning now in China.'' Mr Hung said 90 per cent of the retail space at Times Square was committed under lease at an average rate of more than $70 a sq ft. Meanwhile, only 40 per cent of Tower B in the office complex had been leased at rates lower than $30 a sq ft. The uncertain political situation in Hongkong was partly blamed for the soft office market. Mr Hung said the company had seen its share price rise from $11 in early 1992 to a high of $18.60. The debt to assets ratio was 12 per cent, while the debt to equity ratio was around 17 per cent. The breakdown of contribution to profit by activity was 70 per cent rental income - which is not expected to grow significantly - 18 per cent from transport, four per cent from hotels and the remainder from telecoms. Activities in China, set to become between 10 and 20 per cent of group balance sheet value, were still in a start-up situation, along with cable television. Mr Hung said earnings growth would occur when Times Square and Lane Crawford Place in Singapore come on stream this year and Parc Oasis and Gateway contribute in 1994, and over the longer term when the Diamond Hill project was completed in 1996.