Business Functions Library for Excel

    1. Introduction
      1. Introduction
      2. DYear
      3. DMonth
      4. DateYMD
      5. DateSeqNum
      6. IsSeqDate
      7. DayName
      8. MonthName
      9. IsLeap
      10. DaysInMonth
      11. IsAnniversary
      12. WeekNumber
      13. WeekNumberToDate
      14. MonthStart
      15. MonthEnd
      16. NumPers
      17. MostRecent
      18. MostImminent
      19. TimeBaseLengths
      20. AnnSeq
      21. CreateTimeBase
      1. Introduction
      2. DiffY
      3. DiffM
      4. DiffD
      5. DiffP
      1. Introduction
      2. DpY
      3. DpM
      4. DpD
      5. DpP
      6. PrevDateSeq
      7. NextDateSeq
      8. PrevDateList
      9. NextDateList
      10. NextDateCombine
      11. DatePer
      12. EDateBF
      13. DateSeq
      14. DateSeqCombine
      1. Introduction
      2. TpY
      3. TpM
      4. TpD
      5. Occurs
    1. Introduction
      1. Introduction
      2. DpYBD
      3. DpMBD
      4. DpDBD
      5. NextBD
      6. PrevBD
      7. NextDateSeqBD
      8. PrevDateSeqBD
      9. IsBD
      10. NetWorkDaysBF
      11. NextDateListBD
      12. PrevDateListBD
      1. Introduction
      2. Holiday
      3. DescribeHol
      4. WhatHol
      5. IsHol
      6. IsWE
      7. WesternEaster
      8. CreateDate
    1. Introduction
      1. Introduction
      2. MkPmtsSeq
      3. MkPmts
      4. MkPmtsGrow
      5. MkPmtsFcst
      6. MkPmtsSF
      7. MkPmtsLim
      8. MkPmtsLag
      9. MkPmtsLagProf
      10. RePhasePmts
      11. TotPmts
      12. TotPmtsSF
      13. SumBetween
      14. DoBetween
      15. MatchPmts
      16. CarryNeg
      17. CarryPos
      18. MkPmtsX
      19. MkPmtsLagX
      20. MkPmtsIdx
      21. MkPmtsCats
      22. MkPmtsGroup
      1. Introduction
      2. MkPmtsPer
      3. MkPmtsPerGrow
      4. MkPmtsPerFcst
      5. MkPmtsIdxPer
      1. Introduction
      2. MkPmtsGrowMkt
      3. MkPmtsFcstMkt
      4. MkPmtsPerGrowMkt
      5. MkPmtsPerFcstMkt
    1. Introduction
      1. Introduction
      2. GSpread
      3. UniSpread
      4. UniSpreadGrow
      5. SCurve
      6. SCurveGrow
      7. DistSpread
      8. FStepSpread
      9. TStepSpread
      10. MkPmtsWeighted
      11. SCumCurve
      1. Introduction
      2. UniSpreadPer
      3. SCurvePer
      4. SCurveGrowPer
      5. UniSpreadGrowPer
      1. Introduction
      2. WeightSpread
      3. FWeightSpread
      4. TWeightSpread
      1. Introduction
      2. UniSpreadH
      3. SCurveH
      4. WeightSpreadH
      5. FWeightSpreadH
      6. TWeightSpreadH
      7. DistSpreadH
      8. GSpreadH
      9. UniSpreadAdj
      10. SCurveAdj
      11. WeightSpreadAdj
      12. FWeightSpreadAdj
      13. TWeightSpreadAdj
      14. DistSpreadAdj
      15. GSpreadAdj
    1. Introduction
      1. Introduction
      2. Con
      3. ConGrow
      4. AnnGrow
      5. RePhaseCon
      6. AnnRate
      7. ConSF
      8. ConIdx
      9. ConEvent
      1. Introduction
      2. ConPer
      3. AnnGrowPer
      4. ConGrowPer
      1. Introduction
      2. ConGrowMkt
      3. ConFcstMkt
      4. ConFcstGrowMkt
      1. Introduction
      2. ConRevGrow2
      3. ConRev
      4. ConRevGrow
      5. ConRevFcst
    1. Introduction
      1. Introduction
      2. FStep
      3. FStepGrow
      4. FStepGrowX
      5. FStepThenGrow
      6. FStepFcst
      7. FStepGrown
      8. FStepSF
      9. FStepCombine
      10. MultiFStep
      1. Introduction
      2. TStep
      3. TStepGrow
      4. TStepGrowX
      5. TStepThenGrow
      6. TStepFcst
      7. TStepGrown
      8. TStepSF
      9. TStepCombine
      10. MultiTStep
      1. Introduction
      2. FStepGrowMkt
      3. FStepFcstMkt
      4. TStepGrowMkt
      5. TStepFcstMkt
      1. Introduction
      2. FStepRev
      3. TStepRev
      4. FStepRevGrow
      5. FStepRevFcst
      6. TStepRevGrow
      7. TStepRevFcst
      8. FStepThenGrowRev
      9. TStepThenGrowRev
    1. Introduction
      1. Introduction
      2. FittedRate
      3. Ramp
      1. Introduction
      2. InterpedLevel
      3. FittedLevel
    1. Introduction
      1. Introduction
      2. Bal
      3. Level
      4. FLevels
      5. TLevels
      6. FLevelsGrow
      7. TLevelsGrow
      8. FLevelsFcst
      9. TLevelsFcst
      10. FLevelsCombine
      11. FLevelsThenGrow
      12. TLevelsThenGrow
      1. Introduction
      2. FLevelsGrowMkt
      3. TLevelsGrowMkt
      4. FLevelsFcstMkt
      5. TLevelsFcstMkt
      1. Introduction
      2. Grow
      3. GrowFromTo
      4. FGrowStep
      5. TGrowStep
      6. FGrowStepMkt
      7. TGrowStepMkt
      8. GrowMkt
      9. GrowLin
      1. Introduction
      2. Fcst
      3. FcstGrow
      4. FcstCollar
      5. SumFcst
      6. FFcstStep
      7. TFcstStep
      8. IdxFromTo
      1. Introduction
      2. FcstT
      3. TFcstT
    1. Introduction
      1. Introduction
      2. ALevel
      3. FALevels
      4. TALevels
      5. FALevelsGrow
      6. TALevelsGrow
      7. FALevelsFcst
      8. TALevelsFcst
      9. FALevelsThenGrow
      10. TALevelsThenGrow
      11. ALevelGrow
      1. Introduction
      2. FALevelsGrowMkt
      3. TALevelsGrowMkt
      4. FALevelsFcstMkt
      5. TALevelsFcstMkt
      1. Introduction
      2. AGrow
    1. Introduction
      1. Introduction
      2. PVCon
      3. PVAnnGrow
      4. PVConGrow
      5. PVConQ
      1. Introduction
      2. PVTStep
      3. PVTStepQ
      4. PVTStepIC
      5. PVTStepICQ
      6. PVFStep
      7. PVFStepIC
      8. PVFStepQ
      9. PVFStepICQ
      1. Introduction
      2. PVMkPmtsSF
      3. PVMkPmts
      1. Introduction
      2. PVGSpread
      3. PVUniSpread
      4. PVSCurve
      5. PVSCurveGrow
      6. PVDistSpread
      7. PVFStepSpread
      8. PVTStepSpread
      9. PVMkPmtsWeighted
      10. PVSCumCurve
    1. Introduction
      1. Introduction
      2. SimpleToSimple
      3. SimpleToAER
      4. SimpleToCont
      5. SimpleToDF
      6. AERToSimple
      7. AERToCont
      8. AERToDF
      9. ContToSimple
      10. ContToAER
      11. ContToDF
      12. DFToSimple
      13. DFToAER
      14. DFToCont
      1. Introduction
      2. SimpleToSimpleX
      3. SimpleToAERX
      4. SimpleToContX
      5. SimpleToDFX
      6. AERToSimpleX
      7. ContToSimpleX
      8. DFToSimpleX
      9. RateConvert
      1. Introduction
      2. FVM
      3. PVM
      4. PmtM
      5. TermM
      6. IntRateM
      7. PVEGAnn
      8. PVEGAnnM
      9. PVEGPerAnn
      10. PVEGPerp
      11. PVEGPerpM
      12. PVEGPerPerp
      13. SumEGAnn
      14. SumEGAnnM
      15. SumEGAnnCont
      16. SumLGAnn
      17. SumLGAnnM
      18. SumLGAnnCont
      1. Introduction
      2. PVBF
      3. PMTBF
      4. RateBF
      1. Introduction
      2. APRToQuoted
      3. QuotedToAPR
    1. Introduction
      1. Introduction
      2. PVOne
      3. FPVOne
      4. TPVOne
      5. PVOneQ
      1. Introduction
      2. PVA
      3. IRRA
      4. PayBackA
      5. PayBackDiscA
      6. DurationA
      7. AvLifeA
      1. Introduction
      2. PVE
      3. IRRE
      4. PaybackE
      5. PayBackDiscE
      6. DurationE
      7. AvLifeE
      1. Introduction
      2. PVT
      3. IRRT
      4. PayBackT
      5. PayBackDiscT
      6. DurationT
      7. AvLifeT
      8. PVTIC
      9. IRRTIC
      10. PVTX
      11. IRRTX
      12. PVTCX
      13. IRRTCX
      14. PVTR
      15. IRRTR
      1. Introduction
      2. NPVM
      3. IRRM
      4. CorrectionM
      5. CorrectionCont
      6. CorrectionDC
      7. DurationM
      8. AvLifeM
      9. EffTimeM
    1. Introduction
      1. Introduction
      2. Depreciate
      3. DepreciatedValue
      4. DepPoolWIP
      5. DepPoolRatio
      6. DepPool
      7. DepreciatePer
      8. DepreciateGrowPer
      9. DepreciateFcstPer
      10. DepreciateIdxPer
      11. LIFOPrice
      12. LIFOCalc
      1. Introduction
      2. FAvRate
      3. TAvRate
      4. FAvRateTD
      5. TAvRateTD
    1. Introduction
      1. Introduction
      2. LinReg
      3. BestPoly
      4. SignChanges
      5. RSqrdPoly
      6. PolyEqn
      7. CalcPoly
      8. PolyReg
    1. Introduction
      1. Introduction
      2. LookupNum
      3. LookupN
      4. SeekNum
      5. PickNum
      6. SortPick
      7. LookUpNum2D
      8. PickMatrix
      9. LookupNIndex
      10. Seek
      11. SeekList
      12. SortNum
      13. FindIf
      1. Introduction
      2. DoBetweenX
      3. SumCat
      4. SumCats
      5. SumPos
      6. SumNeg
      7. SumDiv
      8. SumBounds
      9. SumSubRange
      10. SumCombine
      11. SelCats
      1. Introduction
      2. Coordinates
      3. WorkSheetName
      4. RefPlus
      5. GetRef
      1. Introduction
      2. MinBetween
      3. MaxBetween
      4. MeanNZ
      5. WeightAv
      1. Introduction
      2. RangeDir
      1. Introduction
      2. SortText
      3. ApplyToList
      4. CombineLists
      5. TransposeNum
      6. Unique
      1. Introduction
      2. Interp
      3. Interpolate
      4. InterpDate
      5. InterpolateDate
      6. Intersection
    1. Introduction
      1. Introduction
      2. Distribution
      3. PartialDependency
      4. DistCumulative
      5. DistUniform
      6. DistTriangular
      7. DistDoubleTri
      8. DistNormal
      9. DistLogNormal
      10. RandNum
      11. NRandom
      12. PickRandom
      13. DescribeDistType
      14. CumProb
    1. Introduction
      1. Introduction
      2. RentGrow
      3. RentFcst
      1. Introduction
      2. FStepRent
      3. FStepRentGrow
      4. FStepRentFcst
      5. FStepRentFcstCollar
      1. Introduction
      2. TStepRent
      3. TStepRentGrow
      4. TStepRentFcst
      5. TStepRentGrowCollar
      6. TStepRentFcstCollar
      1. Introduction
      2. RentFcstR
      3. RentGrowR
      4. FStepRentGrowR
      5. FStepRentFcstR
      6. TStepRentGrowR
      7. TStepRentFcstR
      8. TStepRentGrowSFR
      9. FStepRentGrowSFR
      10. TStepRentFcstSFR
      11. FStepRentFcstSFR
      1. Introduction
      2. CapValue
      3. EqYield
      4. CapValueG
      5. EqYieldG
      6. CapValueGD
      7. EqYieldGD
      8. NomToTrue
      9. TrueToNom
      10. YPP
      11. YPPDef
      12. YPA
      13. YPADef
      14. CapValueGrowGD
      15. CapValueFcstGD
      16. EqYieldGrowGD
      17. EqYieldFcstGD
      1. Introduction
      2. CapValueDCF
      3. EqYieldDCF
      4. CapValueDCFG
      5. EqYieldDCFG
      6. CapValueDCFGD
      7. EqYieldDCFGD
      8. NomToTrueDCF
      9. TrueToNomDCF
      10. YPADefDCF
      11. YPPDefDCF
      12. TheorYield
      13. ImpGrowth
      14. ImpDiscRate
      15. PVRent
      16. TWRR
      1. Introduction
      2. PVRentGrow
      3. PVRentFcst
      4. PVTStepRent
      5. PVTStepRentGrow
      6. PVTStepRentFcst
      7. PVTStepRentGrowR
      8. PVTStepRentFcstR
      9. PVTStepRentGrowIC
      10. PVTStepRentGrowRIC
      11. PVTStepIdxRentGrowR
      12. PVTStepIdxRentFcstR
      1. Introduction
      2. TStepGTurnRentGrow
      3. TStepGTurnRentGrowR
      1. Introduction
      2. IdxRentGrowR
      3. IdxRentFcstR
      4. IdxRentGrowMktR
      5. IdxRentFcstMktR
      6. TStepIdxRentGrowR
      7. TStepIdxRentFcstR
      1. Introduction
      2. LetCostR
      3. LetCostRQ
      4. LeasingFeeGrowR
      5. FServChargeR
      6. ServChargeGrowR
      7. ServChargeFcstR
      8. FServChargeGrowR
      9. FVacServChargeR
      10. VacServChargeGrowR
      11. VacServChargeFcstR
      12. LeasingFeeFcstR
      1. Introduction
      2. UKRatesGrow
      3. UKRatesFcst
      4. UKRatesGrowR
      5. UKRatesFcstR
      6. UKEmptyRatesFcstR
      7. UKEmptyRatesGrowR
      1. Introduction
      2. LeaseEnd
      3. ReletOccurs
      4. RentDateInfo
      5. RentEventOccurs
      6. RentEvent
      7. LastReview
      8. NextReview
      9. LastReviewR
      10. NextReviewR
      11. LeaseInfo
      12. Occupancy
      13. LeaseDates
    1. Introduction
      1. Introduction
      2. Interest
      3. FInterest
      4. TInterest
      5. TotInterestSF
      6. InterestX
      7. PVFInterest
      8. PVInterestX
      9. PVInterest
      1. Introduction
      2. ZeroCoupon
      3. FutureToSpot
      4. SpotToSpot
      1. Introduction
      2. Loan
      3. LoanX
      4. LoanLin
      5. LoanLinX
      6. Mortgage
      7. MortgageQ
      8. LoanPool
      9. MortgagePool
      10. IdxBondGrow
      11. IdxBondFcst
      1. Introduction
      2. Overdraft
      3. CashAcct
      4. FlexAcct
      5. CurrentAcct
      6. STDAcct
      7. LoanAcct
      8. LoanAcctEM
      1. Introduction
      2. BetaIndex
      3. BetaReturns
      4. DescribeReturn
      5. TotalReturn
      1. Introduction
      2. OptionBS
      3. OptionBinom
      4. OptionMonte
    1. Introduction
      1. Introduction
      2. STOIIP
      1. Introduction
      2. Decline
      3. DeclineRate
      4. DescribeDecline
      5. ProdProf
      6. AbandonDate
      7. StartDecline
    1. Introduction
      1. Introduction
      2. MoneyText
      1. Introduction
      2. GetToken
      3. GetTokens
      4. InString
      5. ExInt
      6. ExFl
    1. Introduction
      1. Introduction
      2. StdEq
      3. DiffGaps
      4. AddGaps
      1. Introduction
      2. SRound
      3. SFloor
      4. SCeiling
      5. RoundWeekDay
      6. RoundMonthDay
      7. RoundMD
      8. RoundDateSeq
      9. DateRound
      10. DateFloor
      11. DateCeiling
      12. Disperse
      13. RoundList
      1. Introduction
      2. BFVer
      3. DescribeLoanAcctOutput
      4. DescribeCombineSwitch
      5. DescribePmtsPerYear
      6. DescribeLevelSwitch
      7. DescribeBD
      8. DescribeDayCount
      9. DescribePeriods
      10. DescribeLookup
      11. DescribeRounding
      12. DescribeLoanOutput
      13. DescribeShape
      14. ArgValues
      1. Introduction
      2. Switch
      3. SwitchR
      4. SwitchT
      5. SwitchRT
      6. IfElse
      7. IfElseR
      8. IfElseT
      9. IfElseRT
      1. Introduction
      2. CollarDate
      3. InBetween
      4. Collar
      1. Introduction
      2. Ev
Note: In order to use the spreadsheet examples, you need to download Business Functions
FutureToSpot (FromDate, ToDate, BaseDate, ToDates, FutureRatesAER, [RateType], [DCount])
Calculate a Spot Rate given a series of Future Rates
This function works out the effective APR interest rate from FromDate to ToDate given a range of input FutureRatesAER. The future rates apply to the corresponding ToDate and run from the preceding ToDate. Both this function and its companion funct
Methodology

Business Functions has functions for converting interest rates from Spot Rates to Future Rates and back again.

  • Spot Rates are rates that are quoted in the financial markets for a fixed period of time from a Base Date until a date in the future e.g. the 10 year spot rate is 8%, i.e. it is 8% fixed for 5 years. The Spot Rate is the overall rate that gets you from the Base Date to Time B.
  • Future Rates are the underlying forecast of interest rates that together combine to produce the Spot Rate. For example, 6% today rising to 12% in 10 years time might give an overall Spot Rate of 9.5%. If a Spot Rate is what gets from A to B, Future Rates are the rates you passthrough along the way.
  • In BF it is assumed that these rates are annual equivalent rates (AER"s), and that interest is compounded until maturity. This is in order that the following approximation can be made.
  • The SpotToSpot and FutureToSpot are the a simple approach to converting rates from one to the other. Derivatives traders actually use more complex formulae, see the Zero Coupon functions in the library such as ZeroCouponDF. SpotRate and FutureRate ignore the frequency of coupons and in effect assume that the SpotRate is a pure discount rate. Now, because SpotRates assume coupons are paid out alongthe way (they are looked up from bond and treasury rates) they are actually not pure discount rates, but can be approximated to discount rates.
  • The method used by SpotToSpot and FutureToSpot is that the NPV is the same under each formula. So for a given time the NPV at the SpotRate is the same as the NPV at the range of FutureRates specified.

It was mentioned above that SpotToSpot is not as sophisticated as the method professional derivatives traders use. It is however a very good workmanlike approximation that does have intellectual "purity" inasmuch as the reverse of SpotToSpot is FutureToSpot, and vice versa. The two areas it does not address are:
  • Payment Frequency. Quoted Spot Rates have a variety of frequencies - semi-annual, quarterly, even annually. These functions assume AER interest rates.
  • The discounting/compounding rate should be the Zero Coupon Rate. These function use the spot or future rates supplied - not quite the same thing, but close enough for a lot of analytical work.

Example
FutureToSpot.xls  

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