I would want to use QuantLib Python to calculate DV01 of an interest rate swap.
Initially I was thinking of calculating the fixed leg DV01 and floating leg DV01 separately, then add both legs DV01 together to get the swap DV01. However, I don't know how to calculate the floating leg DV01 using QuantLib Python.
In the end I took a different approach to calculate interest rate swap DV01 using the following code:
from QuantLib import *
# global data
calendar = TARGET()
todaysDate = Date(6,November,2001);
Settings.instance().evaluationDate = todaysDate
settlementDate = Date(8,November,2001);
# market quotes
deposits = { (1,Weeks): 0.0382,
(1,Months): 0.0372,
(3,Months): 0.0363,
(6,Months): 0.0353,
(9,Months): 0.0348,
(1,Years): 0.0345 }
swaps = { (2,Years): 0.037125,
(3,Years): 0.0398,
(5,Years): 0.0443,
(10,Years): 0.05165,
(15,Years): 0.055175 }
# convert them to Quote objects
for n,unit in deposits.keys():
deposits[(n,unit)] = SimpleQuote(deposits[(n,unit)])
for n,unit in swaps.keys():
swaps[(n,unit)] = SimpleQuote(swaps[(n,unit)])
# build rate helpers
dayCounter = Actual360()
settlementDays = 2
depositHelpers = [ DepositRateHelper(QuoteHandle(deposits[(n,unit)]),
Period(n,unit), settlementDays,
calendar, ModifiedFollowing,
False, dayCounter)
for n, unit in [(1,Weeks),(1,Months),(3,Months),
(6,Months),(9,Months),(1,Years)] ]
fixedLegFrequency = Annual
fixedLegTenor = Period(1,Years)
fixedLegAdjustment = Unadjusted
fixedLegDayCounter = Thirty360()
floatingLegFrequency = Semiannual
floatingLegTenor = Period(6,Months)
floatingLegAdjustment = ModifiedFollowing
swapHelpers = [ SwapRateHelper(QuoteHandle(swaps[(n,unit)]),
Period(n,unit), calendar,
fixedLegFrequency, fixedLegAdjustment,
fixedLegDayCounter, Euribor6M())
for n, unit in swaps.keys() ]
# term structure handles
discountTermStructure = RelinkableYieldTermStructureHandle()
forecastTermStructure = RelinkableYieldTermStructureHandle()
# term-structure construction
helpers = depositHelpers + swapHelpers
depoSwapCurve = PiecewiseFlatForward(settlementDate, helpers, Actual360())
swapEngine = DiscountingSwapEngine(discountTermStructure)
# 5Y Swap
nominal = 1000000
maturity = calendar.advance(settlementDate,5,Years)
fixedLegFrequency = Annual
fixedLegAdjustment = Unadjusted
fixedLegDayCounter = Thirty360()
fixedRate = 0.04
floatingLegFrequency = Semiannual
spread = 0.0
fixingDays = 2
index = Euribor6M(forecastTermStructure)
floatingLegAdjustment = ModifiedFollowing
floatingLegDayCounter = index.dayCounter()
fixedSchedule = Schedule(settlementDate, maturity,
fixedLegTenor, calendar,
fixedLegAdjustment, fixedLegAdjustment,
DateGeneration.Forward, False)
floatingSchedule = Schedule(settlementDate, maturity,
floatingLegTenor, calendar,
floatingLegAdjustment, floatingLegAdjustment,
DateGeneration.Forward, False)
swap = VanillaSwap(VanillaSwap.Receiver, nominal,
fixedSchedule, fixedRate, fixedLegDayCounter,
floatingSchedule, index, spread,
floatingLegDayCounter)
swap.setPricingEngine(swapEngine)
discountTermStructure.linkTo(depoSwapCurve)
forecastTermStructure.linkTo(depoSwapCurve)
print('Fixed Leg DV01')
print(swap.fixedLegBPS())
shift = 0.0001
temp_fyc_handle = YieldTermStructureHandle(depoSwapCurve)
temp_dyc_handle = YieldTermStructureHandle(depoSwapCurve)
shiftedForwardCurve = ZeroSpreadedTermStructure(temp_fyc_handle, QuoteHandle(SimpleQuote(shift)))
shiftedDiscountCurve = ZeroSpreadedTermStructure(temp_dyc_handle, QuoteHandle(SimpleQuote(shift)))
discountTermStructure.linkTo(shiftedDiscountCurve)
forecastTermStructure.linkTo(shiftedForwardCurve)
P_p = swap.NPV()
temp_fyc_handle = YieldTermStructureHandle(depoSwapCurve)
temp_dyc_handle = YieldTermStructureHandle(depoSwapCurve)
shiftedForwardCurve = ZeroSpreadedTermStructure(temp_fyc_handle, QuoteHandle(SimpleQuote(-shift)))
shiftedDiscountCurve = ZeroSpreadedTermStructure(temp_dyc_handle, QuoteHandle(SimpleQuote(-shift)))
discountTermStructure.linkTo(shiftedDiscountCurve)
forecastTermStructure.linkTo(shiftedForwardCurve)
P_m = swap.NPV()
dv01 = (P_m - P_p) / 2.0
print('Swap DV01')
print(dv01)
Am I correct in how to use QuantLib Python to calculate interest rate swap DV01? The output of the code above shows that the fixed leg DV01 is smaller than the entire swap's DV01. Is that right?