DUBAI, Oct 15 (Reuters) - Shares in Saudi Arabia's Saudi Kayan tumbled on Thursday after the petrochemical manufacturer swung to a third-quarter loss, weighing on the kingdom's index.
Kayan, an affiliate of Saudi Basic Industries - Corp (SABIC) , fell 8.3 percent after announcing a quarterly loss of 13.8 million riyals ($3.7 million) in the three months to Sept 30. That compares with a profit of 66.9 million riyals in the same period a year earlier.
Analyst forecasts were varied, ranging from loss of 120 million riyals to a profit of 38.8 million riyals.
Saudi petrochemical producers benefit from subsidised feedstock while product prices are linked to oil so the sustained slump in crude prices has hurt their margins.
SABIC was down 0.3 percent as eight of Saudi's 10 largest stocks made slight declines and none rose.
The main benchmark fell 0.5 percent to 7,748 points, taking its losses to 15 percent in the second half of 2015.
In Doha, property developer Mazaya Qatar fell 2.9 percent after saying it may increase its capital; it gave no further details.
Mazaya, which accounted for more than a third of shares changing hands on Doha's index, it also said its net profit rose to 92.5 million riyals in the third quarter from 87.9 million riyals a year earlier.
The benchmark was down 0.1 percent at 11,747 points as of 0831 GMT. (Reporting by Matt Smith; Editing by Alison Williams)