The housing market in Groningen province has been ‘seriously’ shaken by the earthquake threat, according to university researchers.

In total, 180,000 houses have lost a combined €1bn in value because of the quake risk, the Groningen University researchers said.

Most of the lost value is in the nine local authority areas most prone to quakes but even in Groningen city itself, house prices have gone down, the researchers said.

The average loss is around €5,000, or 3% of the value. However, this calculation is based on the price of houses which have been sold and does not take into account the fact some houses are now impossible to sell, RTV Noord said.

In Loppersum, which is the epicentre of many quakes, houses prices have gone down by 12%, the researchers say.

The research will play an important role in the forthcoming court case about compensation for home owners in the region, broadcaster RTV Noord said.

Gas company NAM, a 50:50 joint venture between Shell and ExxonMobil, is appealing against a lower court ruling which said all home owners in the province should be compensated for the loss of value because of the quake risk.