House prices in the Netherlands rose by an average of 9.3% in June compared to a year earlier, national statistics office CBS and the land registry Kadaster said on Tuesday. Sales prices were also up 0.9% on May, the CBS said.

House prices rose most sharply in the province of Drenthe, where existing homes were 13.4% more expensive than a year earlier.

Eight out of the 12 provinces saw price growth above the national average, including Groningen, Gelderland and Overijssel which all grew by over 11%.. Noord-Holland and Zeeland had the smallest increases, at 7.1% and 7.2% respectively.

Among the four largest cities, Utrecht recorded the biggest price increase at 10.4%. Prices in Rotterdam rose by 8.7%, while Amsterdam saw a below-average increase of 4.3%.

The CBS figures reflect agreements which have been registered with the Kadaster and lag behind those provided by estate agents association NVM. It said earlier this month that prices had actually fallen by 0.4% in Amsterdam over the past quarter.

The Kadaster registered 18,883 housing transactions in June, nearly 29% more than in the same month last year. In the second quarter, 57,412 homes changed hands—a rise of 19.8% compared to a year earlier.

Sales surged in the big cities as landlords continued to sell off small apartments which are now covered by rent controls. Amsterdam saw the largest increase in transactions, up 37.3%, followed by Utrecht (32.8%), The Hague (22.7%) and Rotterdam (22.2%).