Comma needed on the bold?

Hi, Andrew,

@Andrew Van Wagner posted:

See the bold (I'm anti-comma wherever possible):

he manages Stop Human Rights Violations in Sri Lanka, which is a Facebook group with 2900 members

There is some vacillation around this matter, as you can read here:

Exceptions to digit grouping

The International Bureau of Weights and Measures states that "when there are only four digits before or after the decimal marker, it is customary not to use a space to isolate a single digit".^[30] Likewise, some manuals of style state that thousands separators should not be used in normal text for numbers from 1,000 to 9,999 inclusive where no decimal fractional part is shown (in other words, for four-digit whole numbers), whereas others use thousands separators and others use both. For example, APA style stipulates a thousands separator for "most figures of 1,000 or more" except for page numbers, binary digits, temperatures, etc.

There are always "common-sense" country-specific exceptions to digit grouping, such as year numbers, postal codes, and ID numbers of predefined nongrouped format, which style guides usually point out.

Thanks!