STRONG earnings growth from swift land price rises and steep rental increases last year should combine with expansion in price/earnings ratios to continue inflating the value of property stocks, according to a report by Salomon Brothers. Property shares should increase by a ''modest'' 18 per cent this year. This should rise to 23 per cent in 1995 and 26 per cent in 1996, the report said. It added that property stocks would outperform the rest of the market this year. The wide profit margins generated by the pre-sale of residential units late last year and the high price levels set during the fourth quarter will be reflected in 1995 returns. The report noted that since many developments in Hong Kong were pre-sold 12 to 18 months ahead of completion, profits recorded in any one financial year did not reflect price increases made in that year. Therefore, a property developer's 1994 earnings would not reflect true profitability, which would, by then, be enlarged by the significant profit increases of the fourth quarter of 1993. The report said fears of economic and social disruptions because of the 1997 change of sovereignty, had now all but disappeared. It said the market could no longer be viewed as a ''bubble'' set to burst. The tight labour market, which caused increases in salaries, and limited land supply would also favour the future of property stocks. ''. . . In Hong Kong, personal income increases the affordability of property, which leads to increased demand for floor space. ''The Government's annual land sale programme is fixed at 50 hectares. This has contributed to a price-intensive supply of land. The supply of large and readily developable sites, mostly from the private sector, is difficult to secure. ''The near one-to-one relationship between personal incomes and residential property prices is demonstrated by the fact that while the price of a flat in Hong Kong has advanced 300 per cent over the past decade, so has per capita GDP [Gross Domestic Product],'' the report said.