Tokyo, March 8 (Bloomberg) -- Japanese businessinvestment posted its biggest gain in almost four years in thethree months ended Dec. 31, prompting some economists toraise their economic growth forecasts. Capital spending by companies, excluding the financeindustry, rose 7.1 percent in the fourth quarter from a yearearlier to 11.3 trillion yen ($94.5 billion), following a 0.2percent increase in the third quarter, the Ministry of Financesaid. The report prompted economists to raise their forecasts forfourth-quarter growth -- now seen at 0.3 percent -- becausethe figures are used to calculate the capital spendingcomponent of gross domestic product. That boost may beshort-lived, however, because a slowdown in the U.S.economy is prompting companies to put expansion on holdthis quarter. ``Today's numbers may be like the final flare in a fireworksdisplay,'' said Yasukazu Shimizu, an economist at AozoraResearch Institute Ltd. ``Given we've already seen a bigplunge in exports and a slowdown in industrial output, we canassume the current growth momentum is waning.'' More signs the surge may be short-lived were released today-- the ministry's index of business confidence fell this quarter.Confidence has dipped amid concern the economy is on theverge of recession again. Export volumes dropped for the firsttime in 20 months in January, while industrial productionposted the biggest fall in more than five years.