How should I write long numbers in comma separated lists or parenthetical phrases?

In writing out a sentence with a parenthetical number, it occurred to me that it is a bit difficult to read. Is there a better way? (Yes, this is a bit of a contrived example and yes, I realize it could be reworded to take away the awkwardness, but it illustrates my question)

The database contains a lot of records, nearly 300,000, per month.

When I read this sentence, my eyes do a double-take at the end of "300,000," to comprehend the meaning because with the comma I'm expecting another triplet of digits.

Solution 1:

There's two other ways of adding asides that are almost entirely interchangeable with commas: m-dashes or parentheses. Using your example they'd be:

• The database contains a lot of records--nearly 300,000--per month.
• The database contains a lot of records (nearly 300,000) per month.

The meaning is the same, but the punctuation is less confusing.

Solution 2:

You can work around the problem by writing "three hundred thousand", in words.

If it were up to me, though, I would work around the problem by either using a space as a thousands separator (like this: "300 000"), or by omitting the thousands separator altogether (like this: "300000").

In general, I don't feel that thousands separators are obligatory. After all, your car's odometer doesn't have one, and you almost certainly don't miss it.