The aim is to help in the decision of where to focus fieldwork and in the writing of proposals for fund raising purposes. These in turm are measured as overall degree of endangerment times special degree of documentation need, where endangerment is the inverse of estimated language vitality and special documentation need is the inverse of the estimated sufficiency of existing special documentation. The language vitality score is calculated from eight different factors such as age of youngest speaker, number of speakers, percentage of monolingual speakers etc.
Most linguists know that the number of human languages in use is rapidly decreasing.
Estimates of the rate of disappearance vary between 12 and 50 a year. It seems obvious that where it is not possible to save these languages, they should at least not die without leaving a trace, that is without being documented in a satisfactory way. The international community of linguists is not unaware of this situation. Still, there remains a lot to be done. We have to talk politicians, institutions, responsible into giving money not only for the preservation and documentation of species of birds and insects, but also of cultures and languages.