Donald Norris, a professor at the University of Maryland, Baltimore County (I’m starting to get a better class of customer) has written to complain about our singulars and plurals.

“I enjoy reading the Sun, among other things, for the quality of the writing which is almost always very good. However, once in a while a reporter slips and an editor doesn't catch it. Here's one example:

“‘Hopkins officials said they believe the data...WASN'T compromised.’”

“The last time I looked, data was a plural noun...and I tell my students this. Now, if they read the paper (which is doubtful and sad) they'll have this to show me when I remind them that data are, not is.”

I answered that, sadly, there are  problems in the English language for which there is no clear right or wrong, no apt solution. Data is one of them.

Garner's Modern American Usage calls data a "skunked" term, meaning that there is no way to use it without irritating some group of readers.

I know that it is the plural of datum; my daughter holds a degree in Latin and Greek from Swarthmore, and I am well advised to show respect for Latin. But as Garner points out, data has, "since the 1940s, been increasingly treated as a mass noun taking a singular verb," and the singular form is growing increasingly rare, to the extent that using it can look pretentious.
 
The Associated Press Stylebook, the basis for The Sun's house style, says emphatically, "A plural noun, it normally takes plural verbs and pronouns." Then, the weasel entry: "See the collective nouns entry, however, for an example of when "data" may take singular verbs and pronouns."

Scientific usage appears to use data increasingly as a collective noun in a singular sense, as does computer science. The language appears to be headed irreversibly in that direction, and I am loath to engage our copy desk in a pointless struggle.

Would God that data were our only problem. (At least we still have some of the subjunctive with us.) There is widespread misunderstanding among journalists about Taliban, which is a plural that the news media (still a plural) insist on making singular. The singular form, talib, means “student.”

And a year ago, my learned colleague Bill Walsh got into a tussle on the American Copy Editors Society’s discussion board over the sentence "An additional $18 billion in six-month bills was auctioned at a discount rate of 4.545 percent." He insisted on were, and the fur flew. Actually, either usage can be justified. If the $18 billion is considered to be a total sum, it can legitimately be considered a singular subject. (Five bushels is what my truck will hold.) But it’s hard to insist that 18 billion of anything are a singular. So context and intent should govern the decision.

Except, as with data, context is often of little help. Go figure.