Housing markets on the Big Island and Kauai in January stayed true to last year’s trend, with mostly higher sales and lower median prices, according to statistics from Hawaii Information Service.

The only exception to the trend last month as well as last year was the submarket for single-family homes on Kauai, where sales were down and the median price was up.

There were 29 single-family homes sold in January on the Garden Island, down slightly from 31 in the same month last year. The median price was $420,000 compared with $375,000 in the same period.

In Kauai’s condominium market, the number of sales rose 43 percent to 20 last month from 14 a year earlier. The median price was down 10 percent to $300,750 from $335,000.

The condo market on the Big Island showed the biggest surge in sales, with a 48 percent rise to 43 transactions last month compared with 29 a year earlier. The median price was down 18 percent to $219,000 from $265,500. Single-family home sales on the Big Island were up 17 percent to 103 last month from 88 a year earlier. The median price slipped 6 percent to $220,000 from $234,250.

Because the activity on the two neighbor islands is relatively light, changes in the median price are subject to more influence from the mix of homes sold as opposed to any difference in inherent property values.

The median price is the midpoint at which half the sales were at a higher price and half were at a lower price. So, a higher proportion of million-dollar resort home sales can boost the market’s broader median price.

Such a situation appears to have happened with single-family homes on Kauai last month. Seven of the 29 sales were in Hanalei, which includes Princeville Resort. The median price for the seven Hanalei homes was $1.3 million. A year earlier there were six Hanalei home sales for a median $447,500.

Correction: Sales figures in the above chart are for January 2011 and January 2010. An earlier version of this story incorrectly said the sales were for January 2010 and January 2009.