Did Special Housing Areas help?

A while back I went and had a looksie at some local Special Housing Areas near me in Auckland.

I wasn't hugely impressed. At the first one I went to look at, I felt that designating it an SHA didn't seem to have made any material difference either way. On the left, by the way, is the very latest state of play on that first SHA site I visited. Still a long way from being finished - no dramas, it's the developers' prerogative to set whatever schedule best suits them - but not an obvious example of SHA status moving things along.

On a follow-up visit I had more doubts, noting that non-SHA apartment blocks were going up all over the place but the SHA sites were somnolent. "I'd like to believe", I said, that "Special Housing Areas greased the wheels of the housing planning process, and either accelerated or increased new construction, or both ... But how will anyone definitively know? ... I'm hoping that someone - an economic consultant with an interest in housing, maybe? - will be asked to turn their minds to a proper 'with and without' exercise: matching a bunch of otherwise similar SHA and non-SHA areas, and checking to see if the SHA ones outperformed in speed or quantity".

Another visit left me asking the same questions. "it still leaves me with a nagging feeling that the interesting Special Housing Area initiative (faster planning approval in exchange for including some 'affordable' housing) didn't work out as everyone had imagined. We need to know whether this policy experiment worked, and if it did, repeat it or widen it, and if not, why. Otherwise we'll continue to blunder around with well-intentioned housing ideas that never get properly evaluated".

Lo and behold, someone's actually done exactly that "proper 'with and without' exercise: matching a bunch of otherwise similar SHA and non-SHA areas". It's just been published in the online version of New Zealand Economic Papers as "Price effects of the special housing areas in Auckland": the abstract is here and if you've got access to NZEP online, here's the link to the full article. It's by Mario Fernandez of Auckland Council's Research and Monitoring Unit and two co-authors, Gonzalo Sánchez at ESPOL in Ecuador and Santiago Bucaram at the Inter-American Development Bank.

They used a difference-in-differences approach which looked at what happened to house prices in SHAs compared to those in nearby non-SHA areas. Before the SHA experiment, prices in both areas had been rising at about the same rates: assuming (I think reasonably) that those trends would have carried on absent the SHA cunning plan, you can attribute any subsequent differences between SHAs and non-SHAs to the effect of the SHA policy.

The SHA initiative did not scrub up well:

Our findings indicate that the SHA programme caused price increases (inside SHAs) amounting about 5% on dwelling prices and 4% on the price per square metre, and had no effect on the probability of affordable transactions to occur but actually increased the probability of costly transactions. These results cast doubts on the reliability of the SHAs as a housing policy aimed at improving affordability (p11) ... the findings of this paper suggest that the effectiveness of the SHAs on improving affordability was questionable or negligible (p13)

The findings were robust to the usual econometric tyre kicking (eg allowing for the possibility that developers and buyers saw the SHAs coming and might have changed their behaviour accordingly, and making the comparisons only on SHAs and non-SHA areas that are very close neighbours).

The authors say, "the policy questions that arise are: what weakened the SHA programme? or why
were the affordability requirements not binding to developers?".

On the first, one possibility (they say) is that "the fast-tracking of the consenting process [the SHA deal was faster consents, in exchange for agreeing to build an element of affordable housing] resulted with the developers being able to offer an additional attribute to their products: rapid delivery of new constructions ... Hence, the SHA programme simply allowed developers to offer new homes with an additional attribute (a shorter delivery time), which consequently implied higher prices" (p12).

On the second, there was an element of gaming the system. Developers had the option of waiting to see what planning options might become available under the Auckland Unitary Plan, rather than forging ahead with their SHA consents: "there were expectations of greater profits under the rules of the AUP rather than the SHA programme. Therefore, this could explain why prices did not decrease inside the SHAs as the timing of development may have relied on building first the more profitable (and expensive) houses and later (or never) the affordable" (p12). Scuttlebutt I picked up at the time fits with this explanation.

I'm not going to bag the designers of the SHA: I'm more in the 'let a thousand flowers bloom' camp when it comes to policy experiments, and anything that sounded plausible (the faster consent / affordability combo) was worth a go. I think we all knew that it wasn't going to make much of a difference compared to the impact, say, of a large expansion in the supply of housing-zoned land. But at the margin it might have been a small help.

It wasn't. People more familiar than me with the intricacies of the housing market can carry on the conversation about why not. My takeaway from the whole exercise is that any policy experiment ought to automatically come with follow-up provisions to see how it went. Not rocket science, you'd think, but it's routinely ignored all over the place: we're throwing money in the air, and not checking to see where it drifts or who picks it up. It's time to realise that 'evidence based policy' isn't just about designing a plausible initiative: it also means seeing if it lived up to expectations, and if not, why not.