Prime Minister Lee Hsien Loong said economic growth has been raised to between 7 and 8 per cent for the year in an upbeat National Day message Wednesday, but warned of a widening income gap in the city-state and all over the world, according to dpa. "Economic growth in the first half of this year was 7.6 per cent, higher than expected, Lee said in his televised message. The city- state celebrates its 42nd birthday on Thursday. Delivered for the first time from the top floor of the new National Library Building with the skyline in the background, Lee said, "Singapore is celebrating National Day in a happy mood with four good years of growth." On the economic side, 111,000 jobs have been added in the first half of 2007 and unemployment is at 2.4 per cent. "The region is moving forward," Lee noted. "China and India are powering ahead. South-East Asia has regained its balance" after the currency crisis in 1997. "Singapore is growing not just because of more investments or more workers," Lee said. "Our people are adapting and working smarter." "In short, we have increased our productivity," he said of the export-oriented country. "Our efforts to transform the economy are paying off." Citing a major challenge which could affect social harmony and national cohesion, Lee focused on the "widening of income gaps here and all over the world." One reason is the ageing population, Lee said, adding that the government is making changes to help Singaporeans work longer, earn more and build up their retirement savings. "We are poised to take off," he added.