How Flowing Pennies lets you choose a currency
originally published May 2008; last updated July 2010
There’s an old riddle that goes something like:
If someone who speaks three languages is trilingual...
and someone who speaks two languages is bilingual...
what’s someone who speaks one language?
C’est la vie, but this stereotype fits me perfectly. My lingua franca is English.
At this writing, the most common request for Flowing Pennies
is the ability to use different currencies such as the British Pound £, the Japanese Yen ¥, or the Euro €.
My personal experience (not) using different currencies mirrors my personal
experience (not) speaking different languages. This is new territory for me; so this article is my way of
articulating how it works, where I’m coming from, and how you and I can work forward from here.
There are many issues that come into play when considering the best way for a household finances
application like Flowing Pennies to
let you choose what currency it uses.
Just like the porridge in the story of “Goldilocks and the Three Bears,” software design
is often a struggle to strike just the right balance between opposite extremes.
At one extreme, a finance application could just always show financial balances with the same numbers, and extract
the currency from the system. So if you have your OS X system set for € it would always show the finances
in euros. (Of course, if you then loaded that document on a Japanese system it might show the values in yen ¥.)
At the other extreme, a very sophisticated and complicated solution might be to allow each transaction to use its own currency.
Maybe you pay for breakfast with dollars $ and lunch with euros €. But
Flowing Pennies is designed very fundamentally
to show a running tally of your household finances, as a single number.
So if different transactions within a document are using different currencies, suddenly conversion between currencies
would be required.
But currency conversions fluctuate from day to day, or even from second to second. Trying to track your finances
rigorously when the underlying ratios are varying so unpredictably is just asking for trouble.
(Hopefully) “Just Right”
Flowing Pennies 1.2 takes a middle approach. Now, when
you create a new Flowing Pennies document, it defaults the
currency to whatever your OS X system is set to. But if you bring up
Flowing Pennies’ Preferences dialog, you can edit the
currency for a given document. This makes it possible for one
Flowing Pennies document to be tracked in dollars $ and
another document to be tracked in euros € if that’s what you want.
One of the ways that Flowing Pennies keeps it simple
is that there is no conversion between currencies.
When you change the currency used for a given Flowing Pennies
document, it only changes the format with which the values are shown.
Was this the right direction in which to take Flowing Pennies?
The goal was to find a pragmatic balancing point between Flowing
Pennies’ old behavior (which was, to paraphrase Henry Ford, “You can use any
currency, as long as it’s dollars”) and a fraught-with-peril, overly-complicated potential
currency conversion between any transactions.
Hopefully we found the sweet spot. Our euro-using and yen-using beta testers have reported satisfaction with
Flowing Pennies’ implementation, but we are
eager to hear your opinion. If you have suggestions or (especially!) complaints, please
let us know.
Who knows what the future will be? Que sera sera.
Now that Flowing Pennies might use a currency without
pennies, does its name even make sense any more? ¡Ay, caramba!
What will be the Clarkwood Software response to people who contact
us about improvements and refinements to currency selection (and other features) in
Flowing Pennies? Domo arigato.