PROPERTY development by Kumagai Gumi (HK) rescued the construction firm's earnings for the 12 months to the end of September, when net profits rose 14.8 per cent to $250.25 million. The results were still below market expectations of around $275 million, according to The Estimate Directory . Earnings per share on a fully diluted basis rose 8.55 per cent to 72.5 cents. A final dividend of 12 cents a share took the total to 30 cents, up five cents or 20 per cent from last year's total. Turnover and profit in construction was down, said the company: ''Property development continued to account for a significant portion of the group's profit in 1992.'' The turnover figure fell 5.56 per cent to $2.46 billion. Operating profit slumped by 32.96 per cent amid fierce competition in Hongkong construction to $83.48 million, its lowest since 1989. This took the operating profit margin to 3.38 per cent from 4.7 per cent in 1991, 4.05 per cent in 1990 and 2.26 per cent in 1989. A boost to the profit and loss account came from the booking of sales at Sceneway Garden and New Ocean Centre. Contributions from associate companies were the highest in more than five years at $214 million, compared with $137.42 million in the previous period. The company said that at the end of the financial period it had $3 billion worth of contracts in hand, compared with a declared $4.5 billion in hand at the end of 1991. However, in November a further $1.46 billion contract for the Lantau fixed crossing was awarded. Pre-sales of property development Silver Valley Garden, in Haikou, was reported to have begun, and development projects in Shenzhen, Dongmen and the Yangpu Economic Development Zone have also been announced.