Spokane, WA-based Avista Utilities is seeking approval from the Idaho Public Utilities Commission (PUC) to decrease its rates covering the cost of natural gas by 7.8%, effective Nov. 1. About half of a retail natural gas utility customer’s bill is covered by the purchased gas cost adjustment, and the rate is adjusted to reflect current wholesale costs for gas supplies, weather factors, and storage. If the PUC approves the decrease, average residential and commercial customers would see a decrease of about $4.65 monthly. The PUC will take comments on the proposal through Oct. 11.