Hong Kong Census and Statistics Department announced Thursday the seasonally adjusted unemployment rate dropped from 4.3 percent in May-July to 4.2 percent in June- August.The underemployment rate also declined from 2 percent to 1.9 percent.The number of unemployed persons was 167,500 from June to August, about the same as 167,400 in May to July. The number of underemployed persons fell by around 2,400 from 72,900 to 70,500.The Secretary for Labor and Welfare Matthew Cheung Kin-chung indicated that the labor supply was expected to drop as some of the youngsters, who had joined the workforce du