Currency codes in Numbers

I'm not up on currency codes and the ISO standard but you can create and use your own custom formats if the built-in formats are not to the standard.

Select a cell or cells. In the sidebar on the right, in the Cell tab, create a custom format for those cells. This one is an example of an "accounting style" Euro format. Accounting style has the EUR lined up on the left and the value on the right. I added a tab between the EUR and the rest of the format to make that happen. To insert the tab, you have to hold down the option key (Option Tab).

If you want your decimal points to line up properly in true accounting style (note how they are staggered in the screenshot) you need to add a few refinements so your Custom Format looks something like this:

First: On the left drag up a space token and set it to 'Flexible' like this:

Second: On the right drag up a space token and set it to Normal.

Third: Add a rule for 0. I just typed a - followed by a few spaces.

Fourth (if necessary): Go to the Text panel and reset Alignment to the right:

Now, it should display proper accounting style with decimals aligned, etc..

SG

That does look a lot better.