Пример #1
0
    def test_zero_curve(self):
        rate_helpers = build_helpers()
        settings = Settings()

        calendar = TARGET()

        # must be a business Days
        dtObs = date(2007, 4, 27)
        eval_date = calendar.adjust(pydate_to_qldate(dtObs))
        settings.evaluation_date = eval_date

        settlement_days = 2
        settlement_date = calendar.advance(eval_date, settlement_days, Days)
        # must be a business day
        settlement_date = calendar.adjust(settlement_date)

        ts_day_counter = ActualActual(ISDA)
        tolerance = 1.0e-2

        ts = PiecewiseYieldCurve('discount',
                                 'loglinear',
                                 settlement_date,
                                 rate_helpers,
                                 ts_day_counter,
                                 tolerance)

        # max_date raises an exception...
        ts.extrapolation = True
        zr = ts.zero_rate(Date(10, 5, 2027), ts_day_counter, 2)
        self.assertAlmostEqual(zr.rate, 0.0539332)
Пример #2
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    def test_yield(self):

        rates_data = [('Libor1M',.01),
                  ('Libor3M', .015),
                  ('Libor6M', .017),
                  ('Swap1Y', .02),
                  ('Swap2Y', .03),
                  ('Swap3Y', .04),
                  ('Swap5Y', .05),
                  ('Swap7Y', .06),
                  ('Swap10Y', .07),
                  ('Swap20Y', .08)]

        settlement_date = pydate_to_qldate('01-Dec-2013')
        rate_helpers = []
        for label, rate in rates_data:
            h = make_rate_helper(label, rate, settlement_date)
            rate_helpers.append(h)

            ts_day_counter = ActualActual(ISDA)
            tolerance = 1.0e-15

        ts = PiecewiseYieldCurve.from_reference_date(
            BootstrapTrait.Discount, Interpolator.LogLinear, settlement_date, rate_helpers,
            ts_day_counter, tolerance
        )

        zc = zero_rate(ts, (200, 300), settlement_date)
        # not a real test - just verify execution
        self.assertAlmostEqual(zc[1][0], 0.0189, 2)
Пример #3
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    def test_extrapolation(self):
        rate_helpers = build_helpers()
        settings = Settings()

        calendar = TARGET()

        # must be a business Days
        dtObs = date(2007, 4, 27)
        eval_date = calendar.adjust(pydate_to_qldate(dtObs))
        settings.evaluation_date = eval_date

        settlement_days = 2
        settlement_date = calendar.advance(eval_date, settlement_days, Days)
        # must be a business day
        settlement_date = calendar.adjust(settlement_date)

        print('dt Obs: %s\ndt Eval: %s\ndt Settle: %s' %
              (dtObs, eval_date, settlement_date))
        ts_day_counter = ActualActual(ISDA)
        tolerance = 1.0e-2

        ts = PiecewiseYieldCurve.from_reference_date(BootstrapTrait.Discount,
                                 Interpolator.LogLinear,
                                 settlement_date,
                                 rate_helpers,
                                 ts_day_counter,
                                 tolerance)

        # max_date raises an exception without extrapolaiton...
        self.assertFalse(ts.extrapolation)
        with self.assertRaises(RuntimeError) as ctx:
            ts.discount(ts.max_date + 1)
        self.assertTrue(str(ctx.exception) in (
            "time (30.011) is past max curve time (30.0082)",
            "1st iteration: failed at 2nd alive instrument"))
Пример #4
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    def bootstrap_term_structure(self, interpolator=Interpolator.LogLinear):
        tolerance = 1.0e-15
        settings = Settings()
        calendar = JointCalendar(UnitedStates(), UnitedKingdom())
        # must be a business day
        eval_date = self._eval_date
        settings.evaluation_date = eval_date
        settlement_days = self._params.settlement_days
        settlement_date = calendar.advance(eval_date, settlement_days, Days)
        # must be a business day
        settlement_date = calendar.adjust(settlement_date)
        ts = PiecewiseYieldCurve.from_reference_date(
            BootstrapTrait.Discount,
            interpolator,
            settlement_date,
            self._rate_helpers,
            DayCounter.from_name(self._termstructure_daycount),
            tolerance,
        )
        self._term_structure = ts
        self._discount_term_structure = YieldTermStructure()
        self._discount_term_structure.link_to(ts)

        self._forecast_term_structure = YieldTermStructure()
        self._forecast_term_structure.link_to(ts)

        return ts
Пример #5
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def example03():
    print("example 3:\n")
    todays_date = Date(13, 6, 2011)
    Settings.instance().evaluation_date = todays_date
    quotes = [0.00445, 0.00949, 0.01234, 0.01776, 0.01935, 0.02084]
    tenors = [1, 2, 3, 6, 9, 12]
    calendar = WeekendsOnly()
    deps = [DepositRateHelper(q, Period(t, Months), 2, calendar, ModifiedFollowing, False, Actual360())
            for q, t in zip(quotes, tenors)]
    quotes = [0.01652, 0.02018, 0.02303, 0.02525, 0.0285, 0.02931, 0.03017, 0.03092, 0.03160, 0.03231,
              0.03367, 0.03419, 0.03411, 0.03411, 0.03412]
    tenors = [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 20, 25, 30]
    swaps =  [SwapRateHelper.from_tenor(q, Period(t, Years),
                                        calendar, Annual, ModifiedFollowing,
                                        Thirty360(), Euribor6M(), SimpleQuote(0)) for q, t
              in zip(quotes, tenors)]
    yield_helpers = deps + swaps
    isda_yts = PiecewiseYieldCurve(BootstrapTrait.Discount, Interpolator.LogLinear, 0,
                                   WeekendsOnly(), yield_helpers, Actual365Fixed())

    spreads = [0.007927, 0.012239, 0.016979, 0.019271, 0.020860]
    tenors = [1, 3, 5, 7, 10]
    spread_helpers = [SpreadCdsHelper(0.007927, Period(6, Months), 1,
                                      WeekendsOnly(), Quarterly, Following, Rule.CDS2015,
                                      Actual360(), 0.4, isda_yts, True, True,
                                      Date(), Actual360(True), True, PricingModel.ISDA)] + \
    [SpreadCdsHelper(s, Period(t, Years), 1, WeekendsOnly(), Quarterly, Following, Rule.CDS2015,
                     Actual360(), 0.4, isda_yts, True, True, Date(), Actual360(True), True,
                     PricingModel.ISDA)
     for s, t in zip(spreads, tenors)]
    isda_cts = PiecewiseDefaultCurve(ProbabilityTrait.SurvivalProbability,
                                     Interpolator.LogLinear, 0, WeekendsOnly(), spread_helpers,
                                     Actual365Fixed())
    isda_pricer = IsdaCdsEngine(isda_cts, 0.4, isda_yts)
    print("Isda yield curve:")
    for h in yield_helpers:
        d = h.latest_date
        t = isda_yts.time_from_reference(d)
        print(d, t, isda_yts.zero_rate(d, Actual365Fixed()).rate)

    print()
    print("Isda credit curve:")
    for h in spread_helpers:
        d = h.latest_date
        t = isda_cts.time_from_reference(d)
        print(d, t, isda_cts.survival_probability(d))
Пример #6
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def example02():
    print("example 2:\n")
    todays_date = Date(25, 9, 2014)
    Settings.instance().evaluation_date = todays_date

    calendar = TARGET()
    term_date = calendar.adjust(todays_date + Period(2, Years), Following)
    cds_schedule =  Schedule(todays_date, term_date, Period(Quarterly),
                             WeekendsOnly(), ModifiedFollowing,
                             ModifiedFollowing,
                             date_generation_rule=Rule.CDS)
    for date in cds_schedule:
        print(date)
    print()

    todays_date = Date(21, 10, 2014)
    Settings.instance().evaluation_date = todays_date
    quotes = [0.00006, 0.00045, 0.00081, 0.001840, 0.00256, 0.00337]
    tenors = [1, 2, 3, 6, 9, 12]
    deps = [DepositRateHelper(q, Period(t, Months), 2, calendar, ModifiedFollowing, False, Actual360())
           for q, t in zip(quotes, tenors)]
    tenors = [2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 20, 30]
    quotes = [0.00223, 0.002760, 0.003530, 0.004520, 0.005720, 0.007050, 0.008420, 0.009720, 0.010900,
              0.012870, 0.014970, 0.017, 0.01821]
    swaps = [SwapRateHelper.from_tenor(q, Period(t, Years),
                                       calendar, Annual, ModifiedFollowing,
                                       Thirty360(), Euribor6M(), SimpleQuote(0))
             for q, t in zip(quotes, tenors)]
    helpers = deps + swaps
    YC = PiecewiseYieldCurve.from_reference_date(BootstrapTrait.Discount, Interpolator.LogLinear,
            todays_date, helpers, Actual365Fixed())
    YC.extrapolation = True
    print("ISDA rate curve:")
    for h in helpers:
        print("{0}: {1:.6f}\t{2:.6f}".format(h.latest_date,
                                             YC.zero_rate(h.latest_date, Actual365Fixed(), 2).rate,
                                             YC.discount(h.latest_date)))
    defaultTs0 = FlatHazardRate(0, WeekendsOnly(), 0.016739207493630, Actual365Fixed())
    cds_schedule = Schedule.from_rule(Date(22, 9, 2014), Date(20, 12, 2019), Period(3, Months),
                            WeekendsOnly(), Following, Unadjusted, Rule.CDS, False)
    nominal = 100000000
    trade = CreditDefaultSwap(Side.Buyer, nominal, 0.01, cds_schedule, Following,
                            Actual360(), True, True, Date(22, 10, 2014), Actual360(True), True)
    engine = IsdaCdsEngine(defaultTs0, 0.4, YC, False)
    trade.set_pricing_engine(engine)
    print("reference trade NPV = {0}\n".format(trade.npv))
Пример #7
0
def make_term_structure(rates, dt_obs):
    """
    rates is a dictionary-like structure with labels as keys
    and rates (decimal) as values.
    TODO: Make it more generic
    """

    settlement_date = pydate_to_qldate(dt_obs)
    rate_helpers = []
    for label in rates.keys():
        r = rates[label]
        h = make_rate_helper(label, r, settlement_date)
        rate_helpers.append(h)

    ts_day_counter = ActualActual(ISDA)
    tolerance = 1.0e-15
    ts = PiecewiseYieldCurve.from_reference_date(
        BootstrapTrait.Discount, Interpolator.LogLinear, settlement_date, rate_helpers, ts_day_counter,
        tolerance
    )

    return ts
Пример #8
0
def dividendOption():
    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    # ++++++++++++++++++++ General Parameter for all the computation +++++++++++++++++++++++
    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

    # declaration of the today's date (date where the records are done)
    todaysDate = Date(24 , Jan ,2012)	# INPUT
    Settings.instance().evaluation_date = todaysDate #!\ IMPORTANT COMMAND REQUIRED FOR ALL VALUATIONS
    calendar = UnitedStates() # INPUT
    settlement_days	= 2	# INPUT
    # Calcul of the settlement date : need to add a period of 2 days to the todays date
    settlementDate =  calendar.advance(
        todaysDate, period=Period(settlement_days, Days)
    )
    dayCounter = Actual360() # INPUT
    currency = USDCurrency() # INPUT	

    print("Date of the evaluation:			", todaysDate)
    print("Calendar used:         			", calendar.name)
    print("Number of settlement Days:		", settlement_days)
    print("Date of settlement:       		", settlementDate)
    print("Convention of day counter:		", dayCounter.name)
    print("Currency of the actual context:\t\t", currency.name)

    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    # ++++++++++++++++++++ Description of the underlying +++++++++++++++++++++++++++++++++++
    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

    underlying_name		= "IBM"
    underlying_price	= 191.75	# INPUT
    underlying_vol		= 0.2094	# INPUT

    print("**********************************")
    print("Name of the underlying:			", underlying_name)
    print("Price of the underlying at t0:	", underlying_price)
    print("Volatility of the underlying:		", underlying_vol)

    # For a great managing of price and vol objects --> Handle
    underlying_priceH  = SimpleQuote(underlying_price)

    # We suppose the vol constant : his term structure is flat --> BlackConstantVol object
    flatVolTS = BlackConstantVol(settlementDate, calendar, underlying_vol, dayCounter)
    
    # ++++++++++++++++++++ Description of Yield Term Structure
    
    #  Libor data record 
    print("**********************************")
    print("Description of the Libor used for the Yield Curve construction") 
    
    Libor_dayCounter = Actual360();

    liborRates = []
    liborRatesTenor = []
    # INPUT : all the following data are input : the rate and the corresponding tenor
    #		You could make the choice of more or less data
    #		--> However you have tho choice the instruments with different maturities
    liborRates = [ 0.002763, 0.004082, 0.005601, 0.006390, 0.007125, 0.007928, 0.009446, 
            0.01110]
    liborRatesTenor = [Period(tenor, Months) for tenor in [1,2,3,4,5,6,9,12]]
    
    for tenor, rate in zip(liborRatesTenor, liborRates):
        print(tenor, "\t\t\t", rate)

    # Swap data record 

    # description of the fixed leg of the swap
    Swap_fixedLegTenor	= Period(12, Months) # INPUT
    Swap_fixedLegConvention = ModifiedFollowing # INPUT
    Swap_fixedLegDayCounter = Actual360() # INPUT
    # description of the float leg of the swap
    Swap_iborIndex =  Libor(
        "USDLibor", Period(3,Months), settlement_days, USDCurrency(),
        UnitedStates(), Actual360()
    )

    print("Description of the Swap used for the Yield Curve construction")
    print("Tenor of the fixed leg:			", Swap_fixedLegTenor)
    print("Index of the floated leg: 		", Swap_iborIndex.name)
    print("Maturity		Rate				")

    swapRates = []
    swapRatesTenor = []
    # INPUT : all the following data are input : the rate and the corresponding tenor
    #		You could make the choice of more or less data
    #		--> However you have tho choice the instruments with different maturities
    swapRates = [0.005681, 0.006970, 0.009310, 0.012010, 0.014628, 0.016881, 0.018745,
                 0.020260, 0.021545]
    swapRatesTenor = [Period(i, Years) for i in range(2, 11)]
    
    for tenor, rate in zip(swapRatesTenor, swapRates):
        print(tenor, "\t\t\t", rate)
    
    # ++++++++++++++++++++ Creation of the vector of RateHelper (need for the Yield Curve construction)
    # ++++++++++++++++++++ Libor 
    LiborFamilyName = currency.name + "Libor"
    instruments = []
    for rate, tenor in zip(liborRates, liborRatesTenor):
        # Index description ___ creation of a Libor index
        liborIndex =  Libor(LiborFamilyName, tenor, settlement_days, currency, calendar,
                Libor_dayCounter)
        # Initialize rate helper	___ the DepositRateHelper link the recording rate with the Libor index													
        instruments.append(DepositRateHelper(rate, index=liborIndex))

    # +++++++++++++++++++++ Swap
    SwapFamilyName = currency.name + "swapIndex";
    for tenor, rate in zip(swapRatesTenor, swapRates):
        # swap description ___ creation of a swap index. The floating leg is described in the index 'Swap_iborIndex'
        swapIndex = SwapIndex (SwapFamilyName, tenor, settlement_days, currency, calendar,
                Swap_fixedLegTenor, Swap_fixedLegConvention, Swap_fixedLegDayCounter,
                Swap_iborIndex)
        # Initialize rate helper __ the SwapRateHelper links the swap index width his rate
        instruments.append(SwapRateHelper.from_index(rate, swapIndex))
    
    # ++++++++++++++++++  Now the creation of the yield curve

    riskFreeTS = PiecewiseYieldCurve.from_reference_date(BootstrapTrait.ZeroYield,
            Interpolator.Linear, settlementDate, instruments, dayCounter)


    # ++++++++++++++++++  build of the underlying process : with a Black-Scholes model 

    print('Creating process')

    bsProcess = BlackScholesProcess(underlying_priceH, riskFreeTS, flatVolTS)


    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    # ++++++++++++++++++++ Description of the option +++++++++++++++++++++++++++++++++++++++
    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    
    Option_name = "IBM Option"
    maturity = Date(26, Jan, 2013)
    strike = 190
    option_type = Call 

    # Here, as an implementation exemple, we make the test with borth american and european exercise
    europeanExercise = EuropeanExercise(maturity)
    # The emericanExercise need also the settlement date, as his right to exerce the buy or call start at the settlement date!
    #americanExercise = AmericanExercise(settlementDate, maturity)
    americanExercise = AmericanExercise(maturity, settlementDate)
    
    print("**********************************")
    print("Description of the option:		", Option_name)
    print("Date of maturity:     			", maturity)
    print("Type of the option:   			", option_type)
    print("Strike of the option:		    ", strike)



    # ++++++++++++++++++ Description of the discrete dividends
    # INPUT You have to determine the frequece and rates of the discrete dividend. Here is a sollution, but she's not the only one.
    # Last know dividend:
    dividend			= 0.75 #//0.75
    next_dividend_date	= Date(10,Feb,2012)
    # HERE we have make the assumption that the dividend will grow with the quarterly croissance:
    dividendCroissance	= 1.03
    dividendfrequence	= Period(3, Months)
    dividendDates = []
    dividends = []


    d = next_dividend_date
    while d <= maturity:
        dividendDates.append(d)
        dividends.append(dividend)
        d = d + dividendfrequence
        dividend *= dividendCroissance

    print("Discrete dividends				")
    print("Dates				Dividends		")
    for date, div in zip(dividendDates, dividends):
        print(date, "		", div)

    # ++++++++++++++++++ Description of the final payoff 
    payoff = PlainVanillaPayoff(option_type, strike)

    # ++++++++++++++++++ The OPTIONS : (American and European) with their dividends description:
    dividendEuropeanOption = DividendVanillaOption(
        payoff, europeanExercise, dividendDates, dividends
    )
    dividendAmericanOption = DividendVanillaOption(
        payoff, americanExercise, dividendDates, dividends
    )


    # just too test
    europeanOption = VanillaOption(payoff, europeanExercise)
    americanOption =  VanillaOption(payoff, americanExercise)

    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    # ++++++++++++++++++++ Description of the pricing  +++++++++++++++++++++++++++++++++++++
    # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    
    # For the european options we have a closed analytic formula: The Black Scholes:
    dividendEuropeanEngine = AnalyticDividendEuropeanEngine(bsProcess)

    # For the american option we have make the choice of the finite difference model with the CrankNicolson scheme
    #		this model need to precise the time and space step
    #		More they are greater, more the calul will be precise.
    americanGirdPoints = 600
    americanTimeSteps	= 600
    dividendAmericanEngine = FDDividendAmericanEngine('CrankNicolson', bsProcess,americanTimeSteps, americanGirdPoints)

    # just to test
    europeanEngine = AnalyticEuropeanEngine(bsProcess)
    americanEngine = FDAmericanEngine('CrankNicolson', bsProcess,americanTimeSteps, americanGirdPoints)


    # ++++++++++++++++++++ Valorisation ++++++++++++++++++++++++++++++++++++++++
        
    # Link the pricing Engine to the option
    dividendEuropeanOption.set_pricing_engine(dividendEuropeanEngine)
    dividendAmericanOption.set_pricing_engine(dividendAmericanEngine)
    
    # just	to test
    europeanOption.set_pricing_engine(europeanEngine)
    americanOption.set_pricing_engine(americanEngine)

    # Now we make all the needing calcul	
    # ... and final results
    print("NPV of the European Option with discrete dividends=0:	{:.4f}".format(dividendEuropeanOption.npv))
    print("NPV of the European Option without dividend:		{:.4f}".format(europeanOption.npv))
    print("NPV of the American Option with discrete dividends=0:	{:.4f}".format(dividendAmericanOption.npv))
    print("NPV of the American Option without dividend:		{:.4f}".format(americanOption.npv))
    # just a single test
    print("ZeroRate with a maturity at ", maturity, ": ", \
            riskFreeTS.zero_rate(maturity, dayCounter, Simple))
Пример #9
0
floatingLegTenor = Period(6,Months)
floatingLegAdjustment = ModifiedFollowing
swapHelpers = [ SwapRateHelper.from_tenor(swaps[(n,unit)],
                               Period(n,unit), calendar,
                               fixedLegFrequency, fixedLegAdjustment,
                               fixedLegDayCounter, Euribor6M())
                for n, unit in swaps.keys() ]

### Curve building 

ts_daycounter = ActualActual(ISDA)

# term-structure construction
helpers = depositHelpers + swapHelpers
depoSwapCurve = PiecewiseYieldCurve.from_reference_date(
    BootstrapTrait.Discount, Interpolator.LogLinear, settlementDate, helpers, ts_daycounter
)

helpers = depositHelpers[:2] + futuresHelpers + swapHelpers[1:]
depoFuturesSwapCurve = PiecewiseYieldCurve.from_reference_date(
    BootstrapTrait.Discount, Interpolator.LogLinear,settlementDate, helpers, ts_daycounter
)

helpers = depositHelpers[:3] + fraHelpers + swapHelpers
depoFraSwapCurve = PiecewiseYieldCurve.from_reference_date(
    BootstrapTrait.Discount, Interpolator.LogLinear, settlementDate, helpers, ts_daycounter
)


# Term structures that will be used for pricing:
discountTermStructure = YieldTermStructure()
Пример #10
0
def example02():
    print("example 2:\n")
    todays_date = Date(25, 9, 2014)
    Settings.instance().evaluation_date = todays_date

    calendar = TARGET()
    term_date = calendar.adjust(todays_date + Period(2, Years), Following)
    cds_schedule = Schedule(todays_date,
                            term_date,
                            Period(Quarterly),
                            WeekendsOnly(),
                            ModifiedFollowing,
                            ModifiedFollowing,
                            date_generation_rule=Rule.CDS)
    for date in cds_schedule:
        print(date)
    print()

    todays_date = Date(21, 10, 2014)
    Settings.instance().evaluation_date = todays_date
    quotes = [0.00006, 0.00045, 0.00081, 0.001840, 0.00256, 0.00337]
    tenors = [1, 2, 3, 6, 9, 12]
    deps = [
        DepositRateHelper(q, Period(t, Months), 2, calendar, ModifiedFollowing,
                          False, Actual360()) for q, t in zip(quotes, tenors)
    ]
    tenors = [2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 20, 30]
    quotes = [
        0.00223, 0.002760, 0.003530, 0.004520, 0.005720, 0.007050, 0.008420,
        0.009720, 0.010900, 0.012870, 0.014970, 0.017, 0.01821
    ]
    swaps = [
        SwapRateHelper.from_tenor(q, Period(t, Years), calendar, Annual,
                                  ModifiedFollowing, Thirty360(), Euribor6M(),
                                  SimpleQuote(0))
        for q, t in zip(quotes, tenors)
    ]
    helpers = deps + swaps
    YC = PiecewiseYieldCurve.from_reference_date(BootstrapTrait.Discount,
                                                 Interpolator.LogLinear,
                                                 todays_date, helpers,
                                                 Actual365Fixed())
    YC.extrapolation = True
    print("ISDA rate curve:")
    for h in helpers:
        print("{0}: {1:.6f}\t{2:.6f}".format(
            h.latest_date,
            YC.zero_rate(h.latest_date, Actual365Fixed(), 2).rate,
            YC.discount(h.latest_date)))
    defaultTs0 = FlatHazardRate(0, WeekendsOnly(), 0.016739207493630,
                                Actual365Fixed())
    cds_schedule = Schedule.from_rule(Date(22, 9, 2014), Date(20, 12, 2019),
                                      Period(3, Months), WeekendsOnly(),
                                      Following, Unadjusted, Rule.CDS, False)
    nominal = 100000000
    trade = CreditDefaultSwap(Side.Buyer, nominal, 0.01, cds_schedule,
                              Following, Actual360(), True, True,
                              Date(22, 10, 2014), Actual360(True), True)
    engine = IsdaCdsEngine(defaultTs0, 0.4, YC, False)
    trade.set_pricing_engine(engine)
    print("reference trade NPV = {0}\n".format(trade.npv))