When introducing formal lists in a report, which punctuation mark is commonly used?

The colon is the punctuation mark commonly used to introduce formal lists in a report. When a writer wants to present a series of items or clarify something with a list, placing a colon beforehand signals to the reader that what follows is related and will expand on or specify the information previously mentioned.

For instance, after stating a general idea or a complete thought, a colon invites the reader to anticipate a detailed enumeration of items, making it clear that what is to follow is directly connected to the preceding statement. This usage adheres to standard grammatical conventions, enhancing clarity and structure in writing.

In contrast, other punctuation marks like hyphens, semi-colons, and apostrophes do not serve this purpose in the context of introducing lists. Hyphens are used for connecting words or splitting syllables, semi-colons typically separate closely related independent clauses, and apostrophes indicate possession or form contractions, all of which do not provide the intended clarity when introducing formal lists.