Data: singular or plural

https://blog.oxforddictionaries.com/2014/04/29/data-media-two-tricky-latin-plurals-handle/

A Quick and Dirty Way to Check Your Writing

Here's a quick and dirty tip to check your own use of data.

If you wish to use data as a singular mass noun, you should be able to replace it in the sentence with the word information, which is also a mass noun. For example,

Much of this information is useless because of its lack of specifics.

If, however, you want to or need to use data as a plural count noun, you should be able to replace it with the word facts, which is also a plural count noun. For example,

Many of these facts are useless because of their lack of specifics.