All the listed fees are subject to an annual price adjustment (for the first time in 2009), which is calculated according to the following formula.
|E||=||Applicable storage fee in €/year or €/month|
|E0||=||Initial value for the storage fee|
|I||=||Average annual value of the German Producer Price Index|
|I0||=||Base value for I; base year 2009 (2005 = 100)|
|L||=||Annual average value of the index of hourly rates in the German energy industry|
|L0||=||Base value for L; base year 2009 (2005 = 100)|