What is the life of a Black Berkey filter?

The amount of filter water from a "Black Berkey" filter element: 11350 liters with faucet water and up to 4 times less with "recovered" water

Life of 2 filter elements: Take an example, at the rate of 12 liters of daily filtration with tap water is obtained a duration of about 5 years (and 1 year and a half to 5 years with water recovered according to the amount of impurities).
An abnormally high limestone rate can significantly reduce the life of the filter filters "Black Berkey"
Average cost of filtration: 0.00675 euros per liter (life of the pair of filter elements "Black Berkey" of 22700 liters).