this process helps to concentrate the urine and increase the volume of water in the blood. Aldosterone acts via a similar method as it acts to increase the production of 3 types of channels: 1) sodium channels.
This means that a new greenhouse costing $20,000 which has a useful life of 25 years would be depreciated at a rate of 8%, twice the straight line rate, of the undepreciated value each year as compared to taking 4% of the original cost each year as the annual depreciation allowance.
That's why, with the exception of land, every capitalized asset is assumed to have a useful life span. Your coolers, for example, might last for 10 years. Over the course of those 10 years, the value of the $15,000 you spent on the coolers gradually leaves the company as the equipment ages and wears down.