What does the "market value" of a CD on TD Ameritrade mean?

External question — Personal Finance Stack Exchange Author: Sophie Swett Original post: https://money.stackexchange.com/questions/113149 License: CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ Adaptation: HTML converted to plain text; contact email addresses removed. Yesterday, I bought my first certificate of deposit. (I did it more for fun and experience than for any other reason.) It's a 1-month CD that I bought on the primary market, with a coupon of 1.9%. I bought just one CD, so I paid $1,000 for it, and if I'm doing the math right, I'm going to get back $1,000 * (1 + 0.019/12) = $1,001.58 when it matures. Anyway, after I bought the CD, I looked at it in my TD Ameritrade account and I saw that—woe is me!—this security which I paid $1,000 for is now worth a mere $999.99: Now, I'm not actually worried about this; I know I'll get back my investment and my buck fifty-eight when the CD matures. But what does TD Ameritrade's listed "market value" for this CD actually mean? It's not the last trade price, is it? It's not the present value; the maturity date is 34 days from now, so by my calculation, the present value at a discount rate of 1.9% is $999.83. I doubt it's a bid price, since that would be an awfully tiny spread. So what is it?