Insurance policies and premiums always refer to an index of the Belgian Association of Surveyors, commonly called the ABEX index.
This index reflects changes in construction prices. Applied to the amount of the premiums payable for insurance cover, irrespective of the type, it increases the value of the risk covered at the same rate.
It is true that if you insured your home for €130,000 in 2003, and it burns to the ground in 2010, the cost of rebuilding your home will be greater than when it was originally built. That is why this index is applied to the amount of your premium as well as to the replacement cost or, as a general rule, the amount of compensation in the event of a claim.
The ABEX index is published twice a year. To check the index for this year and previous years, visit the website of the Belgian Association of Surveyors (http://www.abex.be/). This site contains a complete list of ABEX indices, from 1978 to the present.