THE gross value of construction work in Hongkong was $16.9 billion in the third quarter of last year, 7.7 per cent more than in the same period in 1991. According to the latest survey by the Census and Statistics Department, the increase was largely due to more active construction work on public sites and a significant growth in various non-site construction activities. Compared with the second quarter of last year, the value of construction work increased by 3.9 per cent. Construction work performed on private sites was valued at $7.9 billion, 1.9 per cent down from the same quarter in 1991. This was the result of a drop in work on commercial buildings. Work performed on public sites was valued at $4.3 billion, 16.5 per cent more than a year earlier. The rise was attributed to work starting on some airport-related projects. Residential building projects, valued at $1.6 billion, continued to account for the greatest portion of the value of construction work. The value of construction work on transport projects was 10.9 per cent higher than a year earlier at $1.6 billion.