Steps to calculate the True Count:

1. Obtain the RC through card counting.
2. Eyeball the discard tray, minus the cut card, plus the seen cards on the table to estimate the remaining deck.
3. Round up the remaining deck estimation to the nearest half deck.
4. Divide the RC by the remaining half deck to get the TC estimation.
5. Floor the TC estimation to the nearest integer.

I'm talking about step 3 here.
From a lot of sources I've gone through, all of them suggest rounding up rather than rounding or flooring.
Thus, I always round up my remaining deck. For example, 2.2 decks remaining, I divide by 2.5; 3.7 decks remaining, I divide by 4.
However, in some cases near the end of a shoe, I just feel it's incorrect to round up.

For example, in a 6 deck game, after a round of play, there are no cards on the table.
From eyeballing, I can tell there are 4.4 decks in the discard tray, so there are 1.6 decks remaining.
Since 1.6 decks round up to 2 decks, I would divide by 2 decks, but round down to 1.5 decks provide a more accurate TC.
9/1.6=5.625 Exact
9/2=4.5 Round up
9/1.5=6 Round down

To rephrase my question, should I round down if I can clearly tell that round down gives me a much closer TC estimation?
For example:
1.1 deck round down to 1, rather than round up to 1.5.
0.6 deck round down to 0.5, rather than round up to 1.