If the proportion of immune individuals exceeds this level due to a mass vaccination programme, the disease will die out.
It is expected that by 2030 the proportion of the national population over 60 will exceed 27%.
All the recipes feed 50 people and in the majority of them, the proportion of calories from fat does not exceed 30 percent.
The proportion of Asian Americans at many selective educational institutions far exceeds the national population rate.
Overall, the proportion of international students accepted on a postgraduate course for the 2010 intake exceeds 17%.
By this time, the proportion of pupils from a Portuguese background exceeded that of all others, including British students.
The proportion of dead or missing vines may not exceed 20% of the total number.
In no Hanoverian war did the unfunded proportion of the debt exceed 20 per cent, and it was rarely that high.
In only a few countries did the proportion of women exceed 40%, and that was in Ireland and Greece.
In 1963, the proportion of Taiwan's economy occupied by industry exceeded that of agriculture.