Adjusting storage fees

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.

In this formula the following terms mean:

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)