The New Zealand flag colour scheme is a popular one, even if it lacks uniqueness, a study has found.
The Human Interface Technology Laboratory (HitLab) at the University of Canterbury studied 194 flags and calculated the popularity of all their colour combinations.
The New Zealand flag used the most common combination of three colours - dark blue, red and white. More than 55 per cent of all three-coloured flags used those colours, HitLab acting director Christoph Bartneck said.
HitLab found the colour green in flags could be associated indirectly with poverty, while the more white there was in the flag the higher the per capita GDP.
Red, white, green and dark blue together made up almost 75 per cent of the surface in all flags.
Ideally every country should have a flag that was clearly different from all others, Dr Bartneck said.
"In reality, there are several flags that are easy to confuse with another.
"The flags of Romania and Chad, for example, only differ in their tint of blue."
New Zealand and Australia's flags were also very similar, as were those of the Ivory Coast and Republic of Ireland.
The research could be used to help inform designers in general about colour schemes, Dr Bartneck said.
"It becomes increasingly difficult to create a colour scheme that is popular and unique."
Green was indirectly associated with poverty because many poorer countries in Africa favoured the colour in their flags.
But: "Using a certain colour will not make a country richer or poorer, and neither do countries choose their colours because of their wealth.
"Still, the wealth in this world is not evenly distributed, and neither are the colours of flags."
- The Dominion Post