For the first time in four years, the number of goods passing through the port of Rotterdam has not increased, the Port of Rotterdam reported on Thursday.

By the end of this year, an estimated throughput of up to 442 million tonnes will be reached, the same amount as in 2012. In recent years, the throughput increased by about 1 percent each year.

"The main reason for the lack of growth is the continuing economic slump," Hans Smits, CEO of Port of Rotterdam Authority, said in a press release.

"In the past three years, throughput increased by 1 percent, but that isn't on the cards this year, despite the fact that the second half of the year was better than the first. The port of Rotterdam's total market share remained stable," he added.

Especially the throughput of crude oil declined, mainly due to the weak fuel market in Europe and maintenance shutdowns at the refineries. Container throughput was down as well. The handling of dry bulk such as coal, iron ore and agribulk rose and there also was a slight increase in the throughput of oil products.

"Things are exactly the reverse of last year," said Smits. "Where in 2012 crude oil and oil products provided growth, they have failed this year. Now, coal, ore and scrap and agribulk in particular have increased."

Smits expected the port of Rotterdam to be growing again next year between 1 and 1.5 percent, partly due to an improving economy.

Since January 2013, the sea port of Dordrecht, with a throughput of approximately 3 million tonnes a year, has been operated by the Port of Rotterdam Authority. The Dordrecht throughput was thus included in Rotterdam's figures for the first time this year.