Saudi Arabia, the Arab world’s biggest economy, reported a 21 percent rise in non-oil exports in March as demand for petrochemicals and plastics gained momentum from global economic growth. Non-oil exports increased to 11.4 billion riyals ($3 billion) from 9.4 billion riyals in the year-earlier period, the official Saudi Press Agency reported, citing data from the Central Department of Statistics and Information. Saudi March imports advanced 1 percent to 29.9 billion riyals.