I can exactly see what you want to do – it would work. However I cannot immediately see that I can provide that. The only data we have direct access to is asking price. I have set up standard reports to provide data for the monthly NZ Property Report however this does not seek to set up price band criteria by month.

We have a detailed data warehouse application in production, however we have priorities of work and therefore I cannot see us being able to produce such an analysis for quite a while yet. Will be something though that I will be keen to develop.

I’m not sure what would work best, but one idea I have is this. If you could create a chart for say every year going back quite a few years, they could then be used to make an animated gif. That way it would be possible to see the curve ‘flowing’ to the right as prices generally increase, but also see it ‘ebb’ when they drop back, or even more interesting, change shape if sales in one price range increase/decrease relatively.

What I would love to have is:
1. A spread sheet of the numbers for each chart.
2. The actual sales price, but if that isn’t possible, the asking price.
3. That for say very month going back to the dawn of time

I’m happy to do a bit of work on the numbers to try and create something good, and email it to you to see what you think. I think it could take quite a bit of trial and error to come up with something that works well.
Failing that, just the set of charts (as many as possible), all on exactly the same scale, so they would overlay correctly in an animation.
Failing that, a chart with a column for each year for each sales prices, but I don’t think that would be so easy to see.

I think you will find that in the post I wrote on the introduction of the truncated mean for the asking price metric on the NZ Property Report there is a graph showing the distribution of listings by asking price. I do not have a similar chart for sales.

To your second point – you are absolutely right and this is what is done or should be done by economists and financial journalists. I think the important thing is the access to the data – richer data and that was the point I was seeking to make. How much better the data is becoming to aid our comprehension of the drivers of the market. Making these available and accessible as I have done with the NZ Property Report I hope will assist these economists and financial journalists.

I agree to have a single database of 100% of the sales for statistical analysis is the ultimate – clearly QV focus on this however in comparison to the REINZ their data is less up to date due to the protracted timelines between Unnconditional and legal reporting.

The question though is, would any organisation give up the role of reporting the data as the REINZ does for its commercial / media gain for the betterment of the principle when 90% of the data is still good enough. In the same way as I would not give up the data I have with realestate.co.nz for it to be aggregated with other data to give 100% of the web stats when I can report for 93% of the data.

Personally I think a chart showing the distribution of sales prices for the whole market would give the greatest insight. Yes I know the mass media like an index to quote, but many would prefer transparency.

Your 10 key drivers are of course within the market. I would argue looking outside the market at what drives those factors would give greater insight.
Unemployment and interest rates are obvious examples.

This would ensure “all sales” are used to calculate the new HPI, not just 90-95% of them. Garbage in, garbage out. Anyone else see the logic in this?

You are clearly privy to information which I am not. In my regular discussions with the REINZ (they one of our shareholders) I am not aware that any office or franchise has decided to stop submitting sales data.

From regular meetings I have attended I have seen, if anything a greater alignment to the unique and comprehensive merits of all offices continuing to submit data – the change of structure come November is unlikely in the short term to change any office’s view of the sales statistics.

The fact is that the sales statistics are a critical tool for all offices to be effective in developing marketing proposals and so any office would be shooting themselves in the foot to withdraw data as to do so would cut off their access to the total sales data.