en mixed with other races. For example, if 6% of the children born to Nordish mothers were racially-mixed children whose racial identity was not Nordish, the real Nordish birthrate would be reduced from 1.8 to 1.7 (or from 14% to 19% below the replacement rate of 2.1). To correct this omission Table II is adjusted to allow for the effects on the Nordish population of an intermixture rate of 6% during the period from 1990 to 2000, 10% from 2000 to 2020, 15% from 2020 to 2030, and 20% from 2030-2050. It also allows for the compounding or cumulative effects of intermixture with each new generation (allowing thirty years per generation). The last column, based on zero immigration, lowers the assumed rate of intermixture for the period from 2030 to 2050 to 16.5% on the grounds that the pool of potential non-Nordish mates available for intermixture would be smaller.
In Table I the assumed rates of non-Nordish immigration and births cause a relative decline of the Nordish population in proportion to the others (i.e., in terms of population share), while the assumed Nordish birthrate causes an absolute decline in numbers. In Table II the assumed rate of intermixture increases both the relative and absolute decline in both the proportions and numbers of the Nordish population.
The rate of intermixture is determined by three factors -- the relative proportions of different racial elements in the population, the extent of contact between the races, and the degree of racial discrimination in the selection of mates. The rate of intermixture is effectively limited by the proportions of different races in a population. In a monoracial society different races are not present, resulting in reproductive isolation and the effective prevention of intermixture. If other races are present only as a very small minority the rate of intermixture is still necessarily limited to a low level. When other races are present in numbers equal to or exceeding that of a particular race the potential rate of intermixture for that race is effectively unlimited. Within the given proportions of different races in a population, the actual rate of intermixture is determined by the extent of contact between the races and the degree of racial discrimination in the selection of mates. The greater the extent of contact between the races the higher the rate of intermixture will tend to be. To the degree that contact between the races is minimized or prevented, a degree of reproductive isolation is present which reduces the rate of intermixture. If contact between the races is extensive there is no reproductive isolation and racial discrimination in the selection of mates becomes the only effective limit on the rate of intermixture. If two races are present in equal numbers, and contact between and within the races is equally extensive, so that 50% of the pool of potential mates are from each race, there should be a 50% rate of intermixture if there is no racial discrimination in the selection of mates. If the degree of racial discrimination is 50% the rate of intermixture would be 25%. Although the rate of Nordish intermixture with other races is difficult to predict, it is likely to increase due to a number of interrelated and interacting trends, including increasing proportions of other races in the population and thus in the pool of potential mates, more extensive contact between the races, a decreasing level of racial discrimination in the selection of mates, cultural and ideological influences, and the "snowballing" effect -- the increasing momentum or velocity in the rate of intermixture -- caused by the increasing numbers of mixed-race persons themselves.
Allowing for intermixture, my projections in generation intervals of 30 years for the under-15 age group of the Nordish population in the U.S., which in 1992 was 27.7 million, are as follows: 2020 = 22.4 million; 2050 = 15 million; 2080 = 9 million; 2110 = 5 million; 2140 = 2.7 million (i.e., a 90% reduction in 150 years). This projection is based on the assumption that fully 50% of each Nordish generation w