Modern Finance DayCountFraction

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DayCountFraction

Returns the fraction of a year between two dates on a basis, as an exact Decimal.

Syntax

DayCountFraction( d1, d2, basis )

Examples

#import "std/chrono"
#import "std/money"
using money, chrono

'' The year fraction, EXACT -- an integer over an integer.
dim as LocalDate a = LocalDate( 2026, 1, 1 )
dim as LocalDate b = LocalDate( 2027, 1, 1 )

'' A common year on Act/365F is exactly one.
print ( DayCountFraction( a, b, DAYCOUNT_ACTUAL_365_FIXED ) = DecimalOne( ) )  '' true

'' The same span on Act/360 is MORE than a year, which is the point of
'' the basis rather than a defect.
print ( DayCountFraction( a, b, DAYCOUNT_ACTUAL_360 ) > DecimalOne( ) )       '' true

'' Act/Act splits at each 1 January, so four years spanning one leap
'' year come to exactly 4.
print DayCountFraction( LocalDate( 2023, 1, 1 ), LocalDate( 2027, 1, 1 ), _
                        DAYCOUNT_ACTUAL_ACTUAL_ISDA ).ToString( )              '' 4

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Library: Finance
Category: Finance
Documented under: Nothing Becomes A Keyword
Source: pkg/std/money/fincore.tiko in the tiko repository.