SHANGHAI, Nov 3 (Reuters) - China's major indexes slid on Friday to end the week lower, led by Shanghai stocks posting their worst week since August, as anaemic growth in the nation's service sector in October heightened worries about an economic slowdown.
The blue-chip CSI300 index eased 0.1 percent, to 3,992.70, while the Shanghai Composite Index closed down 0.4 percent at 3,371.74 points.
For the week, CSI300 lost 0.7 percent, while SSEC dropped 1.3 percent.
A private survey showed on Friday that activity picked up slightly in China's services sector in October but growth remained modest and much weaker than historical trends.
The findings, together with other private and official business readings this week, are likely to reinforce views that the economy will slow down in the fourth quarter after racing ahead earlier in the year.
Yang Yewei, strategist at Southwest Securities, forecast that China's economy, which expanded 6.8 percent in the September quarter from a year earlier, will decelerate to 6.6 percent in 2017's final three months, and to 6.5 percent in the first quarter of 2018.
He cited the government's anti-pollution campaigns, slowing property investment and the prospect of tighter liquidity as factors.
Also dampening sentiment, China's securities regulator approved last Friday nine IPOs that will raise a total of 9.5 billion yuan ($1.43 billion), more than double the average funds raised in the past weeks.
That sparked fears more equity supply could come onto the market, pushing the tech-heavy start-up index ChiNextp to a five-week low.
For the day, investors sold shares nearly across the board, with real estate and industrial firms among the biggest casualties.
For the week, material and banking stocks led the retreat with a 2.4 percent and 1.9 percent loss, respectively. ($1 = 6.6211 Chinese yuan renminbi) (Reporting by Luoyan Liu and John Ruwitch; Editing by Shri Navaratnam)