Prices for grade-A offices edged up marginally last month as downward adjustment of rents continued, according to Treasure Land Property Consultants. The agent reported that average office prices in April gained 0.29 per cent to $4,422 per square foot on Hong Kong Island and 0.51 per cent to $3,160 per sq ft in Kowloon. Rents slipped 1.24 per cent month-on-month to $22.21 per sq ft a month on Hong Kong Island and 1.6 per cent to $15.38 per sq ft in Kowloon. Treasure Land said the increase in prices and the fall in rents pressed down the investment yield to 6.03 per cent for offices on Hong Kong Island and 5.84 per cent for Kowloon. Office vacancies continued to rise as a result of the weak economic environment and oversupply. It estimated that the rate of vacancies on Hong Kong Island reached 10.57 per cent, but fell to 4.87 per cent in Tsim Sha Tsui due to strong demand from tenants moving from outside areas. About 62,216 sq ft of grade-A offices were sold last month, worth $253 million, Treasure Land said. This was down 2.9 per cent from March and the value represented a 22.39 per cent fall month-on-month. Offices on Hong Kong Island accounted for 70 per cent of the premises traded. The agent said Shun Tak Centre in Sheung Wan recorded the sharpest rise in price last month to $4,400 per sq ft, up 4.76 per cent from $4,200 per sq ft the previous month. Offices at Nine Queen's Road Central showed the greatest resilience to the market downturn, with prices at $6,300 per sq ft, down 28.4 per cent from early last year. Office prices at Convention Plaza in Wan Chai also were firm at $6,100 per sq ft, but were down 33.7 per cent from early last year. The average decline for grade-A offices since early last year was more than 40 per cent, the agent said. Prices at Bank of America Tower had fallen 42.3 per cent during the period, to $4,500 per sq ft. According to Treasure Land, grade-A office prices in Central increased 1.95 per cent to $5,233 per sq ft last month but rents dropped a further 1.87 per cent to $25.18 per sq ft. Investment yield for Central offices had fallen to 5.77 per cent from 8.03 per cent in October due to the continued fall in rents. There had been four sales of grade-A offices in Central in April - three for premises at Bank of America Tower and one for a 1,425 sq ft unit at Nine Queen's Road. Office prices in Admiralty slipped 0.23 per cent to $4,360 per sq ft and rents fell 2.44 per cent to $22.4 per sq ft. Investment yield was about 6.17 per cent, it said. Five sales were reported in the area last month, all at Lippo Centre. In Wan Chai, grade-A office prices were down 0.47 per cent at $4,240 per sq ft, while rents fell 1.63 per cent to $19.86 per sq ft, Treasure Land said. Some Wan Chai landlords had dropped rents to draw or hold tenants as competition grew because of attractive lease offers at Quarry Bay and Central.