ADDING to the debate surrounding the outlook for Hong Kong's economy and its stock market, SG Warburg Securities has fired a salvo of economic data to support its 10,000-point year-end forecast for the Hang Seng Index. Last week, the market heard Jardine Fleming describe Hong Kong stocks as ''running on empty''. This has stirred a few in the securities industry to spring to the territory's defence, including Baring Securities last week. When Warburg first came out with its 10,000 forecast, it was taken as a bearish stance, at a time when the index had hit record highs surpassing 12,000. With the growing doom and gloom towards Hong Kong, the Warburg perspective seems like something akin to a bull's-eye view. Economist Enzio von Pfeil suggests six per cent growth in gross domestic product (GDP) this year is more likely than the preferred five per cent. He says that much is being made of Hong Kong's reliance on China trade. Many economists and strategists have downgraded the territory on the back of the apparently worsening economic outlook for China. And freight movement and industrial production indicators lend support to this. But there are three indicators for the territory that Warburg is now focusing on. These are: Real Hong Kong dollar M2 money supply, growth of domestic export volume and total export volume. Warburg argues that economic growth this year could be faster than last year as long as the global trade picture keeps improving. According to the July-August edition of The Financial Survey, the median forecast for Hong Kong's real economic growth this year is 5.3 per cent. Warburg believes the figure could be in the region of six per cent. The economy is estimated to have grown by about 5.4 per cent in the first quarter. Real money-supply growth, according to Warburg, was the clear supporting factor, while trade sagged a little. Since the end of the first quarter, the growth rates of total export and import volumes have accelerated. The determinant behind this is exports originating in China and Japan. Meanwhile, domestic export volume is also a sign of life. Here, the United States, Japan and China are key components. Mr von Pfeil asks that, given this background of change, can we quantify its impact on GDP? In other words, what does one percentage point change in real trade do to real GDP? He uses annual percentage changes of real data from the first quarter of 1985 until the fourth quarter of 1993. The conclusion from this is that a one-percentage-point change in Hong Kong's domestic export volume adds 1.4 percentage points to real GDP growth. The reason for this strong impact is the value added by domestic exports is higher per export unit than in the case of re-exports. With re-exports, all that is added to the value are services such as transportation, storage and communication. Given Warburg's expectation that re-exports from China and Japan are on the rise, and that Hong Kong's domestic exports to China, Japan and the US are quickening, then year-end trade figures could be much stronger, according to Mr von Pfeil. In the first four months of the year, all exports rose by 7.6 per cent year-on-year, while domestic exports fell by 8.9 per cent. On Warburg's full-year expectations, all exports could be 10 per cent and domestic exports might drop by five per cent. This is the reason for the brokerage believing in a higher GDP growth figure than the consensus forecast.