When the AKI is used in contracts, the contract text should include:

• Name and abbreviation of the AKI that is used
• Preliminary or final index
• Industry sector of the index figures
• Base month for index calculation, give the index figures for the base month
• Month of calculation
• Number of decimals used when calculating.

Example: A price is be calculated once a year, using the AKI for workers in the engineering industry. When calculating, the preliminary October index should be used.

The AKI shown in the contract text is formulated as AKI, SNI2007 industry 25–30,33, preliminary index. It is very important to clarify if the index should be calculated with the preliminary or definitive index. The difference between these two indexes is that:

• The preliminary index does not contain retroactively paid wages. The index is published 8-9 weeks after the end of the measurement month (see special link to the publishing plan).
• The definitive index contains retroactively paid wages. Publication takes place twelve months after the publication of the preliminary index figures.