where no linguistic estimate is available
i have used an indirect method
based on the percentage of country's population over the age of twenty-five who have completed their secondary or further education
the assumption being that
in a country where the language has official status
and is taught in school
this figure would suggest a reasonable level of attainment
the notion of a variety of english referred to above includes standard
pidgin and creole varieties of English
that is why
in certain country
the usage totals in the list are much higher than would be expected if only standard english were being consider
in nigeria foe example large number use nigerian pidgin englih as a second language
the linguistic justification for this approach is that these variety are, indeed, variety of english
and are usually related to standard along a continuum
on the other hand
because the end of this continuum may be not