Category:Language articles with invalid population dates

This is a maintenance category. It is used for maintenance of the Wikipedia project and is not part of the encyclopedia. It contains pages that are not articles, or it groups articles by status rather than subject. Do not include this category in content categories. This is a hidden category. It is not shown on its member pages, unless the corresponding user preference 'Show hidden categories' is set.

This category is triggered if something other than a purely numerical value is entered in the date field of a language infobox. (Note that this does not happen if a merely unlikely date is entered.) An invalid input affects the display of the infobox as well as its ability to detect obsolete data.

Entering 'NA' or 'no date' in the date field triggers a subcategory. Though it does not cause any problems with display, it does prevent the obsolescence calculation.