About 8% of Аll men and about 0.5% of all women are suffering from color blindness (colour vision deficiency). This means chances that your neighbour or one of your classmates is colorblind are very high.
To put the percentages into perspective – there are close to 300 million people who are colorblind and struggle every day.
99% of all colorblind people are suffering from red-green color blindness.
Interestingly the number affected varies among groups. Isolated communities with a restricted gene pool sometimes produce high proportions of color blindness, including the less usual types. Examples include rural Finland, Hungary, and some of the Scottish islands. By contrast in sub-Saharan Africa there are few colour blind people. Countries such as India and Brazil have a relatively high incidence of colour vision deficients because of the large numbers of people with mixed race genes in their genetic history.
In the United States, about 7 percent of the male population—or about 10.5 million men—and 0.4 percent of the female population either cannot distinguish red from green, or see red and green differently from how others do. More than 95 percent of all variations in human color vision involve the red and green receptors in male eyes. It is very rare for males or females to be “blind” to the blue end of the spectrum.
The 8% of colour blind men can be divided approximately into 1% deuteranopes, 1% protanopes, 1% protanomalous and 5% deuteranomalous. Approximately half of colour blind people will have a mild anomalous deficiency, the other 50% have moderate or severe anomalous conditions.
Numbers of tritanopes/tritanomalous people and achromats is very small, perhaps 1 in 30-50,000 people.
Reliable statistics for people with an acquired form of colour vision deficiency are difficult to find but as many as 3% of the population could be affected because age-related deficiency is relatively common in the over 65s and therefore on the increase in the developed countries due to the rising numbers of elderly people per capita.