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.
Example: You want to calculate how many days a battery will last in an ITE instrument using a 312 size battery. You have measured the Battery Drain at .75 ma and we will use the default Battery Capacity from the table above which is 130 mah. We will assume the user is wearing the hearing aid 16 hours per day.