The LPS calculation in AIMZ uses both known index figures from Statistics Norway (SSB) and estimated figures for future months. The rising line ahead is therefore an estimate, and the estimated amount is included in the LPS forecast and in the figures you see.
How to see which figures are known and estimated
Go to LPS in the left menu.
Click the name of the index.
You see each month with Index, Source (SSB or estimate), cost and posted.
The buttons in the index view
Fetch from SSB: Fetches the latest figures manually if the last month is missing.
Estimate: Creates an estimate for future months.
Edit: Changes the index.
You also see how many payment plans and billing schedules use the index.
Good to know
The calculation is based on the amounts in the billing schedule and the payment plans. If the plans are not updated, LPS will be wrong even if the index is correct.