DUBAI, Oct 16 (Reuters) - Saudi Arabia's Alinma Bank 1150.SE , the kingdom's ninth-largest bank by assets, reported a 16.8 percent fall in third-quarter net profit on Sunday, according to a bourse statement.

* Net profit in the three months to Sept. 30 was 312 million riyals ($83.2 million), compared with 375 million riyals in the same period last year.

* Average forecast of four analysts: 409.1 million riyals.

($1 = 3.7495 riyals)

(Reporting by Tom Arnold; Editing by Mark Potter) ((Tom.Arnold@thomsonreuters.com; +97144536265; Reuters Messaging: tom.arnold.thomsonreuters.com@reuters.net))