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Modelling Energy Forward Curves Svetlana Borovkova Free University of Amsterdam (VU Amsterdam) – Typeset by Foil T E X 1

Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

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Page 1: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Model

ling

Ener

gy

Forw

ard

Curv

es

Sve

tlana

Boro

vkova

Free

Uni

vers

ity

ofA

mst

erda

m(V

UA

mst

erda

m)

–Typ

eset

byFoi

lTEX

–1

Page 2: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Ener

gy

mar

kets

•Pre

-198

0s:

regu

late

den

ergy

mar

kets

•19

80s:

der

egula

tion

ofoi

lan

dnat

ura

lga

sin

dust

ries

•19

90s:

der

egula

tion

ofel

ectr

icity

indust

ries

wor

ldw

ide

•Ener

gyis

the

wor

ld’s

larg

est

trad

edco

mm

odity

clas

s

•Cru

de

oilis

the

wor

ld’s

larg

est

com

modity

•Ener

gym

arke

tsar

eex

trem

ely

vola

tile

(annual

vola

tilit

ies:

Oil

40+

%,

NG

60+

%,

Ele

ctrici

ty10

0+%

−→co

mp.

with

15+

%fo

req

uity

indic

es)

=⇒

nee

dfo

reffi

cien

trisk

man

agem

ent

•Ener

gypr

ices

are

neg

ativ

ely

corr

elat

edto

the

stock

pric

esan

din

dic

es

=⇒

per

fect

div

ersifica

tion

tool

s

What

istr

aded

?

Phys

ical

crude

oil,

oilpr

oduct

s,N

G(s

pot

mar

kets

);fo

rwar

dco

ntr

acts

(OT

C);

Futu

res

contr

acts

onIC

E,N

YM

EX

:vo

lum

es9-

10tim

eshig

her

than

thos

ein

spot

mar

kets

!

–Typ

eset

byFoi

lTEX

–2

Page 3: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Futu

res

contr

act

sand

forw

ard

curv

es

•Fu

ture

s:st

andar

diz

edco

ntr

acts

for

del

iver

yof

aco

mm

odity

(e.g

.cr

ude

oil)

atdiff

eren

t

tim

epoi

nts

(exp

irie

s)in

the

futu

re.

•Price

sfo

rfu

ture

sw

ith

diff

eren

tex

pirie

s(e

.g.,

for

oil,

up

to72

mon

ths

ahea

d)

are

reco

rded

dai

ly.

•T

he

colle

ctio

nof

thes

efu

ture

spr

ices

onan

ypar

ticu

lar

day

isca

lled

the

forw

ard

curv

e.

•T

he

set{F

(t,T

),T

>t}

isth

efo

rwar

dcu

rve

prev

ailin

gat

dat

et

for

agi

ven

com

modity

ina

give

nlo

cation

;T

indic

ates

the

expiry,

orm

aturity

dat

e(m

onth

).

•T

he

forw

ard

curv

eis

the

fundam

enta

lto

olw

hen

trad

ing

com

moditie

s,as

spot

pric

es

may

be

unob

serv

able

and

option

sill

iquid

.

–Typ

eset

byFoi

lTEX

–3

Page 4: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Ben

efits

offo

rwar

dcu

rves

•For

war

dcu

rves

reflec

tm

arke

tfu

ndam

enta

lsan

dan

tici

pat

edpr

ice

tren

ds

•B

ench

mar

kfo

rVal

uat

ion:

Dea

lPrici

ng,

P&

L

•In

tern

alCon

sist

ency

inth

edes

kor

the

firm

with

other

der

ivat

ives

•M

ark

To

Mar

ket,

Sto

pLos

s,VaR

•T

he

forw

ard

curv

espr

ovid

eth

eca

libra

tion

ofth

em

odel

par

amet

ers

under

the

pric

ing

mea

sure

•Com

modity

por

tfol

ios

conta

infu

ture

sw

ith

diff

eren

tex

pirie

s

−→risk

expos

ure

tom

ovem

ents

ofth

een

tire

forw

ard

curv

e

•Prici

ng

ofder

ivat

ives

onfu

ture

san

dfo

rwar

ds

requires

forw

ard

curv

em

odel

s

–Typ

eset

byFoi

lTEX

–4

Page 5: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

The

oil

price

inth

ela

sttw

odec

ades

010

0020

0030

0040

0050

0001020304050607080

$/bbl

Tra

ding

day

s si

nce

23−

06−

1988

WT

I Cru

de O

il pr

ice,

Jul

y 19

98 −

Dec

embe

r 20

06

–Typ

eset

byFoi

lTEX

–5

Page 6: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Oil

forw

ard

curv

es:

two

fundam

enta

lm

arke

tst

ate

sB

ack

war

dation

and

Conta

ngo

Antici

pat

edva

lue

ofth

efu

ture

spot

pric

eis

lower

(B)

orhig

her

(C)

than

the

curr

ent

one.

Influen

ced

by:

curr

ent

pric

ean

din

vento

ryle

vels,

tran

spor

tation

and

stor

age

cost

s,

supply

/dem

and,st

rate

gic

and

pol

itic

alre

ason

s,...

02

46

810

1214

1618

20051015202530

Exp

iry m

onth

s (n

umbe

red

from

now

)

$/barrel

06.0

3.20

00, b

ackw

arda

tion

mar

ket

02

46

810

1214

1618

200246810121416

Exp

iry m

onth

s (n

umbe

red

from

now

)

$/barrel

01.1

2.19

98, c

onta

ngo

mar

ket

–Typ

eset

byFoi

lTEX

–6

Page 7: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Changin

gfa

ceofoil

mar

ket:

arriva

lofhed

ge

funds

Fig

ure

1:W

TIO

ilfo

rwar

dcu

rve,

Mar

ch20

06

–Typ

eset

byFoi

lTEX

–7

Page 8: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sep

tem

ber

2007

–Typ

eset

byFoi

lTEX

–8

Page 9: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalit

yin

com

modity

price

s

•For

oil,

seas

onal

ity

isnot

sign

ifica

nt,

since

tanke

rsar

ere

route

dto

satisf

ya

surg

eof

dem

and

ina

give

nre

gion

•Ener

gy(e

lect

rici

ty,nat

ura

lga

s,sp

ark

spre

ad)

-go

vern

edby

seas

onal

dem

and

•A

gric

ultura

lco

mm

oditie

s(w

hea

t,so

ybea

n,

soym

eal,

crush

spre

ad,

coffee

,co

coa)

-

gove

rned

byse

ason

alsu

pply

•Sea

sonal

ity

inen

ergy

orag

ricu

ltura

lsp

otpr

ices

:

wel

l-under

stood

and

easily

model

led

(e.g

.m

ean-r

ever

sion

with

seas

onal

lyva

ryin

gm

ean,

seas

onal

com

pon

ent

+au

tore

gres

sion

)

•Sea

sonal

ity

info

rwar

dcu

rves

:

much

less

studie

d;no

”exp

licit”

model

s

–Typ

eset

byFoi

lTEX

–9

Page 10: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Exa

mple

ofN

atu

ralG

as

forw

ard

curv

e:

010

2030

4050

6070

6.57

7.58

8.59

9.5

Mon

ths

to m

atur

ity

Sterling pence per thermN

atur

al g

as fo

rwar

d cu

rve,

Mar

ch 7

, 200

7

–Typ

eset

byFoi

lTEX

–10

Page 11: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Futu

res

vs.

spot

price

s:T

heo

ryofSto

rage

Cos

t-of

-car

ryre

lation

ship

(no-

arbitra

gear

gum

ents

):

F(t

,T

)=

S(t

)e[r

(t)+

w(t

)](T

−t)

(∗)

r(t

) :sp

otin

tere

stra

te,w

(t):

mar

ginal

stor

age

cost

sper

$of

spot

,per

tim

eunit.

Inpr

actice

(∗)

alm

ost

nev

erhol

ds

(e.g

.bac

kwar

dat

ion

orhum

p-s

hap

edfo

rwar

dcu

rves

):

stra

tegi

cim

por

tance

(oil)

;lim

ited

ornon

-sto

rabili

ty(a

gric

ultura

l,el

ectr

icity)

Con

veni

ence

ofhav

ing

phys

ical

com

modity

asop

pos

ite

tofu

ture

sco

ntr

act

−→co

nce

pt

ofco

nven

ienc

eyi

eld

y(t

):

F(t

,T

)=

S(t

)e[r

(t)−

y(t

)](T

−t)

-pr

emiu

m(a

spe

rcei

ved

onth

eda

yt)

earn

edby

anow

ner

ofph

ysic

alco

mm

odity

asop

posi

teto

anow

ner

ofth

efu

ture

sco

ntra

ctwith

mat

urity

T.

–Typ

eset

byFoi

lTEX

–11

Page 12: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Conve

nie

nce

yiel

d

•O

ften

consider

ednet

mar

ginal

stor

age

cost

s:y(t

)=

y(t

)−

w(t

).

•Con

venie

nce

yiel

dpr

opor

tion

alto

the

spot

pric

ey(S

):B

rennan

&Sch

war

tz(1

985)

.

•Sto

chas

tic

conve

nie

nce

yiel

dy(t

)=

y(t

,ω):

Gib

son

&Sch

war

tz(1

990)

,Sch

war

tz

(199

7).

•D

epen

den

ceon

t:”p

rem

ium

”to

owner

ofphys

ical

com

modity

chan

ges

with

inve

nto

ries

(sto

cks)

and

hen

ce,w

ith

agen

ts’pr

efer

ence

for

phys

ical

rath

erth

anpap

er.

•At

afixe

ddat

et,

asingl

eva

lue

ofth

epr

oce

ss(y

(t))

tfo

ral

lm

atur

itie

sis

not

com

pat

ible

with

the

hum

p-s

hap

edfo

rwar

dcu

rve

obse

rved

in20

06in

the

oilm

arke

t(a

nd

other

com

modity

mar

kets

),or

with

seas

onal

feat

ure

sof

the

forw

ard

curv

e.

–Typ

eset

byFoi

lTEX

–12

Page 13: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Theo

ryofSto

rage

revi

site

d

•O

ne

pos

sible

model

ling

answ

eris

toin

troduce

ate

rmst

ruct

ure

y(t

,T

)of

conve

nie

nce

yiel

ds

atdat

et,

det

erm

inistic

inth

em

aturity

argu

men

tT

and

stoch

astic

int

(Bor

ovko

va&

Gem

an,20

06,20

07)

•T

his

appr

oach

isce

rtai

nly

ben

efici

alin

the

case

ofse

ason

alco

mm

oditie

ssu

chas

nat

ura

lga

sw

her

e,as

sum

ing

today

=Ja

nuar

y20

08,y(t

,T

)sh

ould

be

diff

eren

tfo

rT

=

Sep

tem

ber

2008

orT

=D

ecem

ber

2008

.

•D

epen

den

ceof

conve

nie

nce

yiel

don

mat

urity

T(y

(t,T

)):

toem

phas

ize

seas

onal

ity

of

F(t

,T

)in

F(t

,T

)=

S(t

)e[r

(t)−

y(t

,T)]

(T−

t)

e.g.

futu

res

expirin

gat

”des

irab

le”

seas

on(e

.g.

NG

futu

res

expirin

gin

Dec

ember

)

Em

phas

izes

the

tim

e-sp

read

option

feat

ure

ofco

nve

nie

nce

.

–Typ

eset

byFoi

lTEX

–13

Page 14: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Forw

ard

curv

em

odel

s

One,

two

and

thre

efa

ctor

model

s:sp

otpr

ice,

conve

nie

nce

yiel

dan

din

tere

stra

te

(Bla

ck(1

976)

,G

ibso

n&

Sch

war

tz(1

990)

,Sch

war

tz(1

997)

)

Futu

res

pric

esar

eder

ived

byno-

arbitra

gear

gum

ents

:F

(t,T

)=

EQ[S

(T)|F

t].

Sea

sonal

com

moditie

s(S

oren

sen

(200

2)an

dLuci

a&

Sch

war

tz(2

002)

):

Two-

fact

orm

odel

sw

ith

seas

onal

spot

pric

ean

da

long-

term

equili

briu

mpr

ice.

Sea

sonal

ity

ente

rsth

efu

ture

spr

ice,

but

not

inan

explic

itan

dco

nsist

ent

way

.

One

step

forw

ard:

Am

in,N

g&

Pirro

ng

(199

4):

seas

onal

(but

det

erm

inistic)

conve

nie

nce

yiel

d,on

efu

ndam

enta

lfa

ctor

:sp

otpr

ice,

cost

-of-ca

rry

rela

tion

ship

.

Mai

ndra

wbac

ksof

allab

ove

model

s:

Spot

pric

eis

not

ago

od

indic

ator

ofov

eral

lst

ate

ofth

em

arke

t.

For

war

dcu

rve’

sse

ason

alfe

ature

sar

enot

take

nin

toac

count

explic

itly

=⇒

Model

sdo

not

mat

chob

serv

edfo

rwar

dcu

rves

.

–Typ

eset

byFoi

lTEX

–14

Page 15: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalco

st-o

f-ca

rry

model

:First

fundam

enta

lfa

ctor

The

aver

age

leve

lof

the

forw

ard

curv

e,or

the

aver

age

forw

ard

pric

epr

evai

ling

atdat

et:

F(t

)=

N√ √ √ √N ∏ T=

1

F(t

,T

),or

lnF

(t)

=1 N

N ∑ T=

1

lnF

(t,T

),

wher

eN

:m

axim

um

liquid

mat

urity

.

•A

ssum

e:(N

mod

12)

=0,i.e.

consider

mat

urities

up

toa

(num

ber

of)

year

(s)

−→th

atway

F(t

)is

not

seas

onal

.

•O

ther

way

sof

const

ruct

ing

anon

-sea

sonal

F(t

) ,so

the

assu

mption

can

be

rela

xed

•N

otlim

ited

tore

gula

rly

spac

edm

aturities

but

can

incl

ude

alltr

aded

liquid

mat

urities

•Can

incl

ude

all(n

otliq

uid

)m

aturities

,by

consider

ing

trad

ed-v

olum

e–wei

ghte

dav

erag

e

–Typ

eset

byFoi

lTEX

–15

Page 16: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalco

st-o

f-ca

rry

model

:Sea

sonalpre

miu

m

The

seas

onal

prem

ium

(s(M

))M

=1,.

..,1

2is

the

colle

ctio

nof

long

-ter

m–a

vera

gepr

emia

(exp

ress

edin

%)on

futu

res

expi

ring

inth

eca

lend

arm

onth

M(M

=1,..

.,12)

with

resp

ectto

the

aver

age

forw

ard

pric

eF

(t) .

•A

ssum

e(s

(1),

...,

s(1

2))

isth

edet

erm

inistic

colle

ctio

nof

12par

amet

ers;

•Req

uire

that

∑12

M=

1s(M

)=

0;

•Sea

sonal

prem

ium

isan

abso

lute

quan

tity

and

not

ara

te:

prem

ium

onfu

ture

sex

pirin

g

inJu

lyis

the

sam

ew

het

her

today

isJu

ne

orD

ecem

ber

.Pre

miu

mon

July

2008

futu

res

is

the

sam

eas

onJu

ly20

09fu

ture

s.

•Can

be

defi

ned

asa

continuou

s-tim

eper

iodic

funct

ion

(e.g

.tr

igon

omet

ric)

;how

ever

less

appr

opriat

efo

rm

onth

lyex

pirie

s.

–Typ

eset

byFoi

lTEX

–16

Page 17: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalco

st-o

f-ca

rry

model

:T

he

model

For

any

mat

urity

T,we

write

F(t

,T

)=

F(t

)e[s

(T)−

γ(t

,T)(

T−

t)] ,

(∗)

wher

eγ(t

,T

),de

fined

byth

ere

lation

ship

(∗),

isca

lled

the

stoc

hast

icco

nven

ienc

eyi

eld

netof

seas

onal

prem

ium

,fo

rm

aturity

T,as

per

ceiv

edon

the

day

t.

Sea

sonal

(mon

thly

)pr

emiu

m(o

rdisco

unt)

:in

s(T

)

Sto

chas

tic

fact

ors

influen

cing

forw

ard

pric

es:

inγ(t

,T

)

The

rela

tion

ship

(∗)

invo

lves

only

forw

ard

pric

es,hen

ceno

inte

rest

rate

s.

–Typ

eset

byFoi

lTEX

–17

Page 18: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Fea

ture

softh

em

odel

Rel

atio

nsh

ipto

clas

sic

conve

nie

nce

yiel

dm

odel

s:

γ(t

,T

)−

s(T

)

T−

t=

y(t

,T

)−

1 N

N ∑ K=

1

y(t

,K

)

−→γ(t

,T

)ca

nbe

inte

rpre

ted

asth

ere

lative

conv

enie

nce

yiel

dne

tof

the

(sca

led)

seas

onal

prem

ium

.

•Con

venie

nce

yiel

can

be

use

dfo

rnon

-sto

rable

com

moditie

s(e

.g.

elec

tric

ity)

,

since

spot

pric

epla

ysno

role

•If

γ(t

,T

)≡

0−→

one-

fact

orm

odel

drive

nby

F(t

)an

ddet

erm

inistic

s(T

)

•If

s(T

)=

0∀T

,th

enno

det

erm

inistic

seas

onal

ity

(e.g

.oi

l)an

dγ(t

,T

)is

the

”rel

ativ

eco

nve

nie

nce

yiel

d”−→

two-

fact

orm

odel

sim

ilar

toG

ibso

n&

Sch

war

tz(1

990)

but

with

F(t

)in

stea

dof

the

spot

pric

e.

–Typ

eset

byFoi

lTEX

–18

Page 19: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Dyn

am

ics

offu

ndam

enta

lfa

ctors

and

futu

res

price

s

F(t

)is

not

seas

onal

byco

nst

ruct

ion

−→ca

nbe

model

led

asa

mea

n-r

ever

sion

with

const

ant

mea

n,or

GB

M.

γ(t

,T

)is

esse

ntial

lyze

ro(o

nav

erag

e),since

allsy

stem

atic

dev

iation

sar

ein

s(T

)

−→ca

nbe

model

led

asa

mea

n-r

ever

sion

with

mea

nze

ro.

All

stoch

astic

conve

nie

nce

yiel

ds

(γT(t

))T

=1,.

..,N

are

drive

nby

the

sam

eB

row

nia

n

mot

ion,in

dep

enden

tof

the

BM

drivi

ng

the

aver

age

forw

ard

pric

e.

Sea

sonal

cost

-of-ca

rry

+dyn

amic

sof

(F(t

),γ

T(t

))=

dyn

amic

sof

(F(t

,T

))T.

Res

ultin

gfu

ture

spr

ices

F(t

,T

)ar

elo

g-nor

mal

with

inst

anta

neo

us

prop

ortion

alva

rian

ce

ξ2(t

,T

)=

σ2+

(ηT(T

−t)

)2−

ρη

T(T

−t)

–Typ

eset

byFoi

lTEX

–19

Page 20: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Model

estim

ation

Histo

rica

ldat

aof

dai

lyfo

rwar

dcu

rves

(F(t

,1),

...,

F(t

,12))

t=1,.

..,n

.

Est

imat

e

•th

edai

lyav

erag

efo

rwar

dpr

ice

byln

F(t

)=

1 12

∑12

M=

1ln

F(t

,M

);

•th

ese

ason

alpr

emia

(s(M

))M

,ac

cord

ing

toth

edefi

nitio

n,by

s(M

)=

1 n

n ∑ t=1

[ln

F(t

,M

)−

lnF

(t)]

,M

=1,..

.,12,

•th

est

och

astic

conve

nie

nce

yiel

dby

γ(t

,T

)=

(−ln

(F(t

,T

)/F

(t))

+s(T

))/((

T−

t)).

Mor

eth

an12

mat

urities

:ea

sily

inco

rpor

ated

,but

iffe

wer

than

12m

aturities

,th

e

unbia

sed

estim

ate

for

F(t

)is

not

avai

lable

−→a

mor

eco

mplic

ated

estim

atio

npr

oce

dure

.

–Typ

eset

byFoi

lTEX

–20

Page 21: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalpre

miu

mfo

rN

atu

ralG

as

futu

res

12

34

56

78

910

11

12

−0.2

−0.1

5

−0.1

−0.0

50

0.0

5

0.1

0.1

5

0.2

0.2

5

0.3

Cale

ndar

month

Seasonal premium in %

Seasonal pre

miu

m for

NG

futu

res

–Typ

eset

byFoi

lTEX

–21

Page 22: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalpre

miu

mfo

rel

ectr

icity

futu

res

12

34

56

78

910

11

12

−0.2

−0.1

5

−0.1

−0.0

50

0.0

5

0.1

0.1

5

Cale

ndar

month

%

Seasonal fo

rward

pre

miu

m, E

lectr

icity futu

res

–Typ

eset

byFoi

lTEX

–22

Page 23: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalpre

miu

mfo

rG

aso

ilfu

ture

s

12

34

56

78

910

11

12

−0.0

3

−0.0

2

−0.0

10

0.0

1

0.0

2

0.0

3

Cale

ndar

month

s

%

Gasoil

seasonal com

ponent

–Typ

eset

byFoi

lTEX

–23

Page 24: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Sea

sonalpre

miu

mfo

rsp

ark

spre

ad

12

34

56

78

910

11

12

−0.6

−0.5

−0.4

−0.3

−0.2

−0.10

0.1

0.2

0.3

0.4

Cale

ndar

month

%

Seasonal fo

rward

pre

miu

m, S

park

spre

ad

–Typ

eset

byFoi

lTEX

–24

Page 25: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Ter

mst

ruct

ure

ofst

och

ast

icfo

rwar

dpre

miu

mvo

latilit

ies,

Gaso

ilfu

ture

s

12

34

56

78

91

01

11

20

0.0

2

0.0

4

0.0

6

0.0

8

0.1

0.1

2

0.1

4

Ma

turity

%

Vo

latility

of

(Ga

mm

a(t

,T))

, T

=1

,...

,12

–Typ

eset

byFoi

lTEX

–25

Page 26: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Ter

mst

ruct

ure

ofst

och

ast

icfo

rwar

dpre

miu

mvo

latilit

ies,

Natu

ralG

as

futu

res

12

34

56

78

91

01

11

20

0.0

5

0.1

0.1

5

0.2

0.2

5

0.3

0.3

5

Ma

turity

%

Vo

latility

of

(Ga

mm

a(t

,T))

, T

=1

,...

,12

–Typ

eset

byFoi

lTEX

–26

Page 27: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

The

seco

nd

state

variable

(sto

chast

icfo

rwar

dpre

miu

m),

for

two

month

sto

matu

rity

,G

aso

ilfu

ture

s,Jan.

2000

-D

ec.

2004

02

00

40

06

00

80

01

00

01

20

0−

0.8

−0

.6

−0

.4

−0

.20

0.2

0.4

0.6

0.8

Ga

so

il c

on

ve

nie

nce

yie

ld,

tau

=2

Tra

din

g d

ays s

ince

13

.01

.20

00

–Typ

eset

byFoi

lTEX

–27

Page 28: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Pro

per

ties

ofth

eco

nve

nie

nce

yiel

d

•All

obse

rved

series

(γ(t

,T))

tca

nbe

model

led

bylo

w-o

rder

auto

regr

ession

(ord

er2

-5)

−→au

tore

gres

sive

stru

cture

can

be

explo

ited

for

-fo

reca

stin

gth

est

och

astic

conve

nie

nce

yiel

d-

fore

cast

ing

mar

ket

conditio

ns

-dev

isin

gm

arke

tin

dic

ator

s-

gener

atin

gpr

ofita

ble

trad

ing

stra

tegi

es•

Con

venie

nce

yiel

dca

nbe

regr

esse

don

econ

omic

fundam

enta

lsan

dex

ogen

ous

mar

ket

variab

les,

e.g.

supply

/dem

and,vo

latilit

y,...

Mea

n-r

ever

sion

par

amet

ers

(T=

2):

elec

tric

ity

gas

gaso

iloi

la

T:

0.07

0.09

0.02

0.01

ηT:

0.16

0.10

0.05

0.04

–Typ

eset

byFoi

lTEX

–28

Page 29: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Rel

ationsh

ipof

γ(t

,T)

tom

arke

tin

dic

ato

rsand

econom

icfu

ndam

enta

ls

Theo

ryof

stor

age

+em

piric

alco

nsider

atio

ns

−→co

nje

cture

sab

out

the

conve

nie

nce

yiel

d:

I.

Itis

pos

itiv

ely

corr

elat

edto

the

over

all

pric

ele

vel

(giv

enby

eith

ersp

otpr

ice

orav

erag

efo

rwar

dpr

ice)

II.It

isneg

ativ

ely

corr

elat

edto

inve

nto

ries

III.It

ispos

itiv

ely

corr

elat

edto

spot

pric

e’s

vola

tilit

y

IV.

Itis

neg

ativ

ely

corr

elat

edto

the

corr

elat

ion

bet

wee

nsp

otan

dfu

ture

spr

ices

.

–Typ

eset

byFoi

lTEX

–29

Page 30: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Conje

cture

I:tr

ue,

espec

ially

forhig

her

matu

rities

:G

aso

il

55.1

5.2

5.3

5.4

5.5

5.6

5.7

5.8

−0.0

50

0.0

5

0.1

0.1

5

0.2

Log F

bar

Stochastic convenience yield, T=12

Sto

chastic c

onvenie

nce y

ield

, T

=12, vs a

vera

ge forw

ard

price

–Typ

eset

byFoi

lTEX

–30

Page 31: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Conje

cture

I:tr

ue,

espec

ially

for

hig

her

matu

rities

:N

G

51

01

52

02

53

03

5−

0.5

−0

.4

−0

.3

−0

.2

−0

.10

0.1

0.2

0.3

0.4

NG

M f

utu

res p

rice

, p

en

ce

/te

rm

Stochastic 6−month convenience yield

Sto

ch

astic c

on

v.

yie

ld v

s N

G M

price

: b

lue

: 0

1.9

7−

03

.00

, re

d:

03

.00

−0

2.0

2

–Typ

eset

byFoi

lTEX

–31

Page 32: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Ext

ract

ing

the

seaso

nalco

mponen

t

Sea

sonal

com

pon

ent

is”k

now

n”

mon

thly

prem

ium

−→ex

trac

tit

from

afo

rwar

dcu

rve.

Ifse

ason

ality

was

the

only

det

erm

inin

gfa

ctor

,th

enw

hat

isle

ftsh

ould

alway

sbe

flat

,but

itis

not

!=⇒

situ

atio

ns

sim

ilar

tobac

kwar

dat

ion/c

onta

ngo

arise:

12

34

56

78

9−

1.5

−1

−0.

50

0.51

Mon

ths

to e

xpiry

Sterling/MWh

De−

seas

oned

ele

ctric

ity fo

rwar

d cu

rve,

27.

06.0

1

12

34

56

78

9−

1

−0.

50

0.51

1.52

2.5

Mon

ths

to e

xpiry

Sterling/MWh

De−

seas

oned

ele

ctric

ity fo

rwar

d cu

rve,

15.

12.0

1

–Typ

eset

byFoi

lTEX

–32

Page 33: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Princi

palCom

ponen

tA

naly

sis

ofth

efo

rwar

dcu

rve

Case

I:in

tere

stra

tes

and

non-s

easo

nalco

mm

oditie

s(o

il)

Afo

rwar

dcu

rve

ofal

mos

tan

ysh

ape

can

be

const

ruct

edby

com

bin

ing

thre

esim

ple

shap

es:

Lev

el,Slo

pe,

Curv

ature

−→Princi

pal

Com

pon

ents

of(F

(t))

t∈N

=(F

1(t

),F

2(t

),..

.,F

N(t

))t∈

N

02

46

810

1214

1618

200

0.050.

1

0.150.

2

0.250.

3

0.35

Exp

iry0

24

68

1012

1416

1820

−0.

5

−0.

4

−0.

3

−0.

2

−0.

10

0.1

0.2

0.3

0.4

Exp

iry0

24

68

1012

1416

1820

−0.

3

−0.

2

−0.

10

0.1

0.2

0.3

0.4

0.5

Exp

iry

First

thre

epr

inci

pal

com

pon

ents

expla

inap

prox

.99

%(!

)of

the

forw

ard

curv

e’s

variab

ility

.

(Litte

rman

&Sch

einkm

ann

’91

for

US

gove

rnm

ent

bon

ds,

Cor

taza

r&

Sch

war

tz’9

4fo

r

copper

)

–Typ

eset

byFoi

lTEX

–33

Page 34: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Princi

palCom

ponen

tsofdaily

retu

rns

02

46

810

1214

1618

200

0.050.

1

0.150.

2

0.250.

3

0.35

Exp

iry0

24

68

1012

1416

1820

−0.

5

−0.

4

−0.

3

−0.

2

−0.

10

0.1

0.2

0.3

0.4

Exp

iry0

24

68

1012

1416

1820

−0.

4

−0.

20

0.2

0.4

0.6

0.81

Exp

iry

Thes

efirs

tth

ree

prin

cipal

com

pon

ents

hav

ecl

ear

econ

omic

inte

rpre

tation

,ex

pla

in95

%of

the

tota

lva

riab

ility

,ca

nbe

trea

ted

asth

em

ain

risk

fact

ors

gove

rnin

gth

efu

ture

spr

ices

’ev

olution

.

–Typ

eset

byFoi

lTEX

–34

Page 35: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Applic

ations

ofPCA

I.For

ecas

ting

mar

ket

tran

sition

s(b

etwee

nbac

kwar

dat

ion

and

conta

ngo

):

•T

he

seco

nd

prin

cipal

com

pon

ent

reflec

tsth

eslop

eof

the

forw

ard

curv

e

•Val

ues

clos

eto

0in

dic

ate

aflat

forw

ard

curv

e(a

nd

hen

ce,pos

sible

tran

sition

)

•D

ue

tosm

oot

htim

e-se

ries

-lik

est

ruct

ure

,it

can

be

use

dto

const

ruct

anin

dic

ator

whic

h

antici

pat

espos

sible

tran

sition

s

Bor

ovko

va,EPRM

mag

azin

e(J

une

2003

).

II.Por

tfol

iorisk

man

agem

ent

and

VaR

estim

atio

n

•First

few

prin

cipal

com

pon

ents

(ofre

turn

s)re

flec

tm

ain

risk

fact

ors

=⇒

the

num

ber

orrisk

fact

ors

isgr

eatly

reduce

d

•T

he

distr

ibution

ofpor

tfol

iore

turn

sca

nbe

appr

oxim

ated

via

the

distr

ibution

ofth

em

ain

risk

fact

ors

•In

apor

tfol

ioco

nte

xt,th

ese

risk

fact

ors

can

be

hed

ged

–Typ

eset

byFoi

lTEX

–35

Page 36: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Princi

palCom

ponen

tIn

dic

ato

r

”Raw

”ve

rsio

n:

proj

ection

ofth

edai

lyfo

rwar

dcu

rve

onth

ese

cond

PC

I(t

)=

N ∑ k=

1

PC

L(2

)k

Fk(t

),

wher

eP

CL

(2)

k(k

=1,..

.,N

)ar

ese

cond

prin

cipal

com

pon

ent

load

ings

ofth

efu

ture

s

pric

esse

ries

.

MA

-sm

oot

hed

vers

ion:

IM

A(t

)=

1 M

M−

1∑ i=

0

I(t

−i)

.

Choi

ceof

M:

take

afa

stan

dslow

mov

ing

aver

age.

–Typ

eset

byFoi

lTEX

–36

Page 37: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Applic

ation

ofth

ePC

indic

ato

rto

Bre

nt

oil

futu

res

Gen

erat

ea

”sig

nal

ofch

ange

”w

hen

the

indic

ator

ente

rsso

me

ε-n

eigh

bor

hood

ofze

ro:

010

020

030

040

050

060

070

080

090

010

00−

1

−0.

50

0.51

1.52

2.53

Day

s

$/bbl

010

020

030

040

050

060

070

080

090

010

00−

15

−10−

5051015

Day

s

$

PC

test

sta

tistic

s w

ith in

term

onth

diff

eren

ces

ε-n

eigh

bor

hood

det

erm

ined

via

the

distr

ibution

ofth

ein

dic

ator

(under

the

null-

hyp

othes

is

ofno

chan

ge),

appr

oxim

ated

byei

ther

Mon

te-C

arlo

orboot

stra

pdistr

ibution

.

–Typ

eset

byFoi

lTEX

–37

Page 38: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

PCA

for

seaso

nalco

mm

oditie

s(e

lect

rici

ty,N

G)

Apply

PCA

todes

easo

nal

ized

forw

ard

curv

esF

(t,T

)exp

(−s(

T))

)Sec

ond

and

third

PCs

for

de-

seas

oned

FC

(firs

tPC

=le

vel)

still

reflec

tth

eslop

ean

dcu

rvat

ure

:

12

34

56

78

9−

0.4

−0.

20

0.2

0.4

0.6

0.81

Mon

ths

to e

xpiry

PC1 loadings

Firs

t prin

cipa

l com

pone

nt lo

adin

gs, d

e−ce

nter

ed, d

e−se

ason

ed e

lect

ricity

FC

12

34

56

78

9−

0.8

−0.

6

−0.

4

−0.

20

0.2

0.4

0.6

Mon

ths

to e

xpiry

PC2 loadings

Sec

ond

prin

cipa

l com

pone

nt lo

adin

gs, d

e−ce

nter

ed, d

e−se

ason

ed e

lect

ricity

FC

–Typ

eset

byFoi

lTEX

–38

Page 39: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Applic

ations

ofPCA

:tr

adin

g

•For

des

easo

nal

ized

forw

ard

curv

es,

situ

atio

ns

anal

ogou

sto

bac

kwar

dat

ion/c

onta

ngo

mar

kets

arise,

inte

rms

ofdev

iation

sfrom

the

”typ

ical

”se

ason

alfo

rwar

dcu

rve.

•H

igh

abso

lute

valu

esof

the

seco

nd

PC

indic

ates

whet

her

futu

res

with

shor

ter

(lon

ger)

expirie

sar

eov

erpr

iced

w.r.t.

”typ

ical

”se

ason

alpr

emiu

m

•A

gain

,use

PC

indic

ator

:th

epr

ojec

tion

ofth

edai

lydes

easo

nal

ized

forw

ard

curv

eon

the

seco

nd

PC.

–Typ

eset

byFoi

lTEX

–39

Page 40: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Princi

palCom

ponen

tIn

dic

ato

rfo

rel

ectr

icity

FC

Ava

lue

ofth

ein

dic

ator

far

from

zero

sign

als

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ifica

nt

dev

iation

from

the

”exp

ecte

d”

seas

onal

forw

ard

curv

epat

tern

:

050

100

150

200

250

−4

−3

−2

−10123

Day

s

PC1 scores

Firs

t prin

cipa

l com

pone

nt s

core

s, d

e−ce

nter

ed, d

e−se

ason

ed e

lect

ricity

FC

Can

const

ruct

profi

table

trad

ing

stra

tegi

esbas

edon

the

indic

ator

.(B

orov

kova

&G

eman

(SN

DE

2006

)).

–Typ

eset

byFoi

lTEX

–40

Page 41: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Concl

usions

•Ext

ract

ing

det

erm

inistic

seas

onal

ity

from

forw

ard

curv

esal

low

sto

study

feat

ure

sob

scure

dby

dom

inan

tse

ason

aleff

ects

(PCA

,co

st-o

f-ca

rry,

trad

itio

nal

term

stru

cture

model

s)

•A

vera

gefo

rwar

dpr

ice

isa

robust

iden

tifier

ofth

eov

eral

lpr

ice

leve

l,m

ore

soth

anth

esp

otpr

ice,

alth

ough

now

nee

dto

take

into

acco

unt

slop

ing

forw

ard

curv

es

•Sto

chas

tic

conve

nie

nce

yiel

dis

aquan

tity

indic

ativ

eof

mar

ket

stat

ean

dec

onom

icin

dic

ator

s;it

can

be

explo

ited

toco

nst

ruct

mar

ket

indic

ator

san

dge

ner

ate

profi

table

trad

ing

stra

tegi

es

–Typ

eset

byFoi

lTEX

–41

Page 42: Modelling Energy Forward Curves Free University of ... · Futures contracts and forward curves • Futures: standardized contracts for delivery of a commodity (e.g. crude oil) at

Per

spec

tive

rese

arch

direc

tions

•Bac

kwar

dat

ion/c

onta

ngo

-lik

epr

ofile

inse

ason

alfo

rwar

dcu

rves

•Applic

atio

ns

ofth

em

odel

toth

eder

ivat

ives

pric

ing

•Rel

atin

gth

est

och

astic

conve

nie

nce

yiel

dto

econ

omic

and

other

exog

enou

sva

riab

lessu

chas

stock

s(s

upply

),ex

trem

ewea

ther

conditio

ns(d

eman

d),

...

.

•Model

ling

the

entire

term

stru

cture

ofco

nve

nie

nce

yiel

ds,

with

anum

ber

ofso

urc

esof

unce

rtai

nty

and

vola

tilit

yfu

nct

ions

•Sea

sonal

term

stru

cture

offu

ture

spr

ices

’vo

latilit

ies

•Applic

atio

ns

ofth

em

odel

toag

ricu

ltura

lco

mm

oditie

s

–Typ

eset

byFoi

lTEX

–42