Days in Inventory. The formula to calculate days in inventory is the number of days in the period divided by the inventory turnover ratio. This formula is used to determine how quickly a company is converting their inventory into sales.
How long do hearing aid batteries typically last? A standard hearing aid battery lasts anywhere from 3 to 22 days, depending on the hearing aid type, battery type and capacity, and the amount of hearing aid use. How do I know if I should change batteries? Change your batteries if sounds become distorted or you have to turn up the volume more than usual.
This means that from the time they are produced, they can sit in the box dormant (non-functioning) without losing any strength. So, when you purchase your hearing aid batteries, look for a box with a date the furthest out: a February 2014 date is better than a September 2013 date, for example. The life expectancy of your hearing aid battery really depends on the type of hearing aid you have and how long you wear them each day.