Ref Prd Start

Function Ref Prd Start within
Bond with keys Bond Ref Prd Start keys returns the start date(s) of the reference period(s) of the referenced bond(s) containing a given reference date
Note the reference period can differ from the corresponding accrual period and is needed in the calculation of the time length of the accrual period by a few day count conventions, such as ACT/ACT(ICMA)

If the settlement date is not explicitly given, it will be set to the bond's settlement date as implied by a trade transaction assumed to occur on the
trade date T₀ (typically today).