>>>Cost=(100*2*10)/(100*365)
>>>
>>So, is my understanding correct that we always use 365 and not the adjusted number?
>>
>>Thanks.
>
>I'm not sure, but I believe most banks use 365 day per year. When I went to school the banks used 30 days per month and 360 days per year, but that was before calculators and standalone computers were invented. :-)

I think I've read somewhere that once upon a time even 300 was used as the base, to simplify the calculation, which is, IMO, another euphemism for dirty trick.