[WIP] MVJ-610 Setting start point figure for rent's tasotarkistus

[NC-jsAhonen]

When the old_dwellings_in_housing_companies_price_index is updated for the first time, the start_price_index_point_figure is set for that rent as well.

If the last year's index point figure doesn't exist yet, the current logic in this PR uses the latest available point figure. This might need to be changed so that it does not set it at all if the last year's point figure is not available yet.

SUGGESTIONS:

• If the logic Change the start_price_index_point_figure from number to string, so for example: 100 => "2020 * 100" This would also reveal the year from which the index point figure comes from, not only the number itself.

[juho-kettunen-nc]

If the last year's index point figure doesn't exist yet, the current logic in this PR uses the latest available point figure. This might need to be changed so that it does not set it at all if the last year's point figure is not available yet.

I agree on latter idea. If the lease begins in 2025, we must not allow 2023 point figure to be used because that would be against the specification.

I think we discussed in some meeting the possibility to leave point figure value empty initially, and fill it in a batchrun (or similar async job) at a later date after the value has been published by StatFi. Two ways to go about it:

• add a periodic batchrun job that queries the database for the latest point figure, and queries all leases with tasotarkistus, and adds the correct point figure value to rents that don't have it saved yet. Maybe one a month or week.
• every time a rent is saved without the point figure, schedule some asynchronous job/batchrun to be executed at a later specified date when the value is known to be available. For example, on last week of June (because tasotarkistus calculations are supposed to be performed on 1.7.).

[juho-kettunen-nc]

If the logic Change the start_price_index_point_figure from number to string, so for example: 100 => "2020 * 100" This would also reveal the year from which the index point figure comes from, not only the number itself.

Or instead use the point figure field to save a reference to the point figure object. It contains all the details related to the figure, including value and year.

[juho-kettunen-nc]

I mark this PR as "changes requested", because the topics in my comments are in discussions:

• filling in the missing index point figures afterwards via a batchrun or similar
• saving a reference to the index point figure object, instead of only the numeric value.