Толковый словарь английского языка - data

noun plural but singular or plural in construction Usage: often attributive Etymology: Latin, plural of datum Date: 1646 factual information (as measurements or statistics) used as a basis for reasoning, discussion, or calculation , information output by a sensing device or organ that includes both useful and irrelevant or redundant information and must be processed to be meaningful, information in numerical form that can be digitally transmitted or processed, Usage: Data leads a life of its own quite independent of datum, of which it was originally the plural. It occurs in two constructions: as a plural noun (like earnings), taking a plural verb and plural modifiers (as these, many, a few) but not cardinal numbers, and serving as a referent for plural pronouns (as they, them); and as an abstract mass noun (like information), taking a singular verb and singular modifiers (as this, much, little), and being referred to by a singular pronoun (it). Both constructions are standard. The plural construction is more common in print, evidently because the house style of several publishers mandates it.