(Yicai Global) Jan. 3 -- Sales of new homes in the southern Chinese city of Shenzhen, the so-called Silicon Valley of the East, tumbled below 30,000 last year for the first time in eight years as tighter home-buying regulations kicked in.

Sales plunged 36 percent to 25,820, Shenzhen Economic Daily reported today, citing data from the city's planning office and land and resources bureau. The figure had held between 30,000 and 50,000 since 2010, peaking at 66,450 in 2015.

More restrictive local policy on residential property purchases was the main cause of 2017's sharp fall off in sales. People without a registered permanent address in the tech hub have been barred from buying unless they have paid social insurance contributions for five straight years, up from two. Phased mortgage rate hikes were another factor putting off buyers, with some opting for homes in the adjacent second- and third-tier cities of Dongguan, Huizhou and Zhongshan.

The average price of a new home in Shenzhen has fallen for 15 months in a row, slipping 12 percent to CNY54,256 (USD8,350) per square meter in December, from CNY61,600 in September 2016. Shenzhen had been caught up in a vicious, unending cycle of rising real estate prices over many years.

Shenzhen logged 73,830 sales of non-new-build homes last year, a 31 percent drop compared with 2016. As new land in the city has become ever scarcer, turnover of such properties now runs at three times that of new ones.