centroid overflow for multipoint with integer coords

centroid just sums all points and divide result on point count, but it should use "extended" type.
Example:
{{x = 989466522, y = 789595328}, {x = 989472652, y = 789598701}, {x = 989481089, y = 789595346}, {x = 989484158, y = 789593666}, {x = 989484932, y = 789586937}, {x = 989482640, y = 789580203}, {x = 989478814, y = 789574309}, {x = 989471911, y = 789576825}, {x = 989466522, y = 789595328}}
Result: {x = 315354648, y = -1483637949}
Expected result: {x = 989476582, y = 789588516}