SHENZHEN - Listed companies in Shenzhen saw a rapid increase in research and development investment in 2017, local authorities said Tuesday.

According to the Shenzhen office of the China Securities Regulatory Commission, the listed companies in Shenzhen, except those in the finance and real estate sectors, spent more than 47.4 billion yuan ($7.3 billion) in R&D investment in 2017, accounting for about 10 percent of the total R&D investment of listed companies across the country.

The number of listed companies with R&D investment exceeding 100 million yuan reached 78 in 2017, and six listed companies invested more than 1 billion yuan each in R&D.

The city's listed manufacturing companies, which have 180,000 R&D and technical personnel, invested nearly 43 billion yuan in R&D investment last year, accounting for 5.9 percent of their gross revenue.