The number of people visiting high streets in the Netherlands has fallen by 20% since 2004, according to research by ABN Amro economists.

This means that on Saturdays, 730,000 fewer people spend time in retail areas and this, as well as the rise of online shopping, is having a knock-on effect on shop vacancy rates, the researchers say.

In 2009, for example, some 5% of high street shops were empty, but this has now risen to 9%, economist Sonny Duijn said.

However, high streets in the bigger cities continue to remain popular and gaps caused by bankruptcies, such as the recent closure of V&D department stores, are being filled quickly, Duijn said.

Last year, for example, 18 international retail chains opened operations in Amsterdam, he said.