[GNC] currency of "value" in stock account

[Lionel Élie Mamane]

On Thu, Nov 11, 2021 at 08:57:40AM -0600, David Carlson wrote:
> One minor additional fact about the GnuCash Stock register, while it
> may not identify the currency underlying individual transaction
> split lines, it does have an indication in the lower left corner of
> the current number of shares identified by the security symbol,
> e.g. IBM and the current value in that security register's base
> currency, identified by the symbol, e.g. $, which is sometimes
> ambiguous, but not the ISO identifier, e.g. USD, which would be
> unambiguous.

That is not entirely correct. The "current value" display in the lower
left corner is in the "Default Currency" that is set up in
Edit / Preferences / Accounts / Default Currency
By default, that is the currency set up by the system's locale system
(LC_MONETARY on Unixy systems).

That is yet another currency than the one shown in Debit/Credit, or
Buy/Sell, columns.

> It is also possible to build a transaction in GnuCash that involves
> additional securities in additional split lines, presumably each
> with different underlying currencies in their respective base
> security accounts, but that would not be an accurate representation
> of the actual trades executed in the brokerage house.

What would be an accurate representation of an actual trade would be:

buy 18 IBM stock @105 USD = DEBIT 1904.74 USD = 18 * 105 USD + 12 EUR
(entered as NET PRICING, as is necessary for lot capital gains/loss processing)
withdraw 1890 USD from USD bank account
withdraw 12 EUR from EUR bank account

or

buy 18 IBM stock @105 USD = DEBIT 1890 USD
(entered as GROSS PRICING)
withdraw 1904.74 USD from USD bank account = CREDIT 1904.74 USD
record expense of 12 EUR in "expenses:bank costs" = DEBIT 14.74 USD = DEBIT 12 EUR

or, when IBM buys European start-up Yoyodyne in an all-stock
transaction and one holds yoyodyne shares:

sell 300 Yoyoydine @6.3 USD = CREDIT 1890 USD
buy 18 IBM stock @105 USD = DEBIT 1890 USD

Or in a mixed stock+cash transaction:

sell 300 Yoyoydine @6 EUR = CREDIT 1800 EUR = CREDIT 1890 USD
buy 9 IBM stock @105 USD = DEBIT 945 USD
deposit 900 EUR in bank account = DEBIT 900 EUR = DEBIT 945 USD

-- 
Lionel