INSURANCE

Northridge Quake Insurance Cost Estimates Top $12 Billion: According to the latest tally by Property Claim Services, an industry-supported group that tracks insurance losses, the January, 1994, temblor caused an estimated $12.5 billion in insured property damage. That figure is nearly 7% higher than that of a previous survey in May. The latest quake estimates are the seventh increase in the damage projection since the first estimate of $2.5 billion was released in February, 1994. The figure has risen because of cost increases in claims already filed, according to Ruth Gastel, vice president of issues analysis at the Insurance Information Institute, another trade group.