Loading the player... Covariance is a measure of the degree to which returns on two risky assets move in tandem. A positive covariance means that asset returns move together, while a negative covariance means returns move inversely.
1. Rotterdam (the Netherlands) This Dutch harbor was the largest in the world, until Shanghai and Singapore grew even larger in 1986. This satellite photo gives an indication of the size of the Port of Rotterdam. (Image via Mannlines) About an hour and a half to the south of Rotterdam is Antwerp, the largest port in Belgium.
The Port of Singapore, Singapore. This port was opened in 1819 by a representative from the British Empire â Sir Stamford Raffles. Since its independence from the British Empire back in 1963, the port flourished. It held the title of the worldâs largest port up until 2011.