247
Theta: change of the option price given a change in t.In other words, theta measures how fa
st the value of the option changes
as time goes by, all other things equal.
Black-Scholes theta of a call with
E = 100, T = 1y, r = 10% p.a. and
σ
=
20% p.a..
(
)
()
p t
Put
d
N
rEe
d T
SN
c t
Call
rT
∂ ∂
=
Θ
−
−
=
∂ ∂
=
Θ
−
:
&
2
2
1
'
:
σ
Derivative securities: Options - Black-Scholes modelGreeks