# Re: [Snowdrift-discuss] How the limit works

```On 08/09/2016 12:37 PM, Michael Siepmann wrote:
>  On 08/09/2016 11:20 AM, Bryan Richter wrote:
>
>> <snip>
>> There are three things being discussed here, so I want to provide
>> space to think about them separately.
>>
>> <snip>
>>
>> Finally, how is the minimum sensible pledge displayed: as a dollar
>> amount, or as a ratio? I think it's clear that the amount should be
>> *calculated* as a ratio, but I'm not certain that *displaying* it as a
>> ratio is best. But I don't actually know. Any opinions here?
>>
>> I'm personally partial to dollar amounts because it provides an
>> (algorithmic) level of indirection. If we say we charge <=10%, and
>> then Stripe changes its fees faster than we can adapt, we'd be lying.
>> But if we say, "We won't charge you for amounts less than 2 bucks",
>> that's totally within our control. We would simply use the ratio as a
>> rough guide for future corrections.
>
> This makes sense to me.  However, if we're displaying a dollar amount I
> do think we do need to round it at least to a quarter or half dollar, so
> it doesn't seem mysteriously arbitrary.  For example, since \$3.66
> corresponds to just under 10%, if we use dollar amounts, I'd suggest
> \$3.75 or \$3.50.  Then in future if we support multiple payment
> processors, they could have different minimums if necessary, which could
> also be changed if they change their fees.  I think dollar amounts are
> easier for the user to understand in terms of knowing what determines
> whether they're charged in a given month, so I'd favor dollar amounts
> provided we round to at least a quarter.  In this case we're using the
> ratio calculation in order to decide on a sensible rounded minimum
> dollar charge, and then allowing the maximum percentage to be a weird
> arbitrary number that we don't present to users. For example if the
> minimum charge for Stripe is \$3.50 then with their current charges, the
> maximum percentage is about 11.2%.  I think that's fine as long as we
> don't talk about percentages to the user.  In other words, I think we
> either say something like "Minimum charge is \$3.50" (but don't make it
> \$3.66) or something like "Maximum percentage is 10%" (but don't make it
> 11.2%).
> ```
```
I'm with Michael actually. I change my vote to 10% max fee.

Also, I strongly support displaying it publicly that way "we only charge
if the fee to processor is less than 10% of the total". If fees change
on us suddenly (unlikely), we can basically complain about sudden fee
changes taking unexpected funds (a common and legitimate case in all fee
increase situations regardless). We'd then say "sorry for the extra fees
this month, Stripe changed fee without enough warning, we've now
adjusted our mechanism accordingly. And that's okay and not really our
fault.

```

signature.asc
Description: OpenPGP digital signature

```_______________________________________________
Discuss mailing list
Discuss@lists.snowdrift.coop
https://lists.snowdrift.coop/mailman/listinfo/discuss
```