HONOLULU (HawaiiNewsNow) - For some time now, Hawaii's skyrocketing rents have been explained with simple economics – not enough supply, too much demand.
But new Census figures suggest something more complicated might be going on.
In the second quarter of 2016, nearly 11 percent of Hawaii's rentals were vacant, Census estimates show. That's up from 8 percent at the same time last year (and a far healthier 5 percent in early 2015), and is on par with states with far more affordable housing markets.
In fact, Hawaii had the sixth-highest rental vacancy rate in the nation during the quarter. Nationally, the vacancy rate was 6.7 percent in the second quarter of 2016.
So, what's behind Hawaii's unexpectedly high rental vacancy rate – and shouldn't a high vacancy rate bring down rents?
Unfortunately, economists say, there aren't simple answers to those questions.
First off, Hawaii's vacancy rate is likely going up for a number of reasons.
Eugene Tian, state economist, said the rental vacancy rate might be legitimately increasing in some areas (such as urban Honolulu) because renters are being priced out or moving into homeownership thanks to a construction boom in Kakaako.
He said some renters are undoubtedly "withdrawing from the market" because of the rising prices, moving in with family or sharing their housing cost burden by getting roommates.
(In the second quarter of 2016, the rental vacancy rate in urban Honolulu was 10.1 percent, up from 7.5 percent in the same period a year ago.)
Meanwhile, economists say, the state's rental housing vacancy rate is also likely going up because of a glut of vacation and seasonal rentals on the Neighbor Islands.
The issue is particularly acute on Kauai and Maui.
Kauai, for example, has a rental vacancy rate approaching 18 percent (up from 6 percent in 2000). Maui County's rental vacancy rate is 26 percent, from 7 percent in 2000, according to a 2015 state housing availability report.
The report concluded that the significant increases in rental vacancy rates on the Neighbor Islands highlighted the "increase in the number of seasonal and vacation units."
In other words, there are lots of available rentals on Kauai and Maui – pushing up the rental vacancy rate – but most aren't available to residents. That means more supply – more rentals – isn't translating to lower rents.
And demand, that's as high as ever, said housing expert Ricky Cassiday.
He has another theory for why the Census data shows Hawaii with rising rental vacancy rates: The survey data itself is flawed.
"That vacancy number makes absolutely no sense," he added.