Chapter 6 - Commidity futures and forwards Flashcards
most important consideration of commodities
they have indivuidual features that affect their price specifically. for instance storage costs.
Recall the established forward price for a financial forwrd contract
F_{0,T} = S_0 e^(r-∂)T
the book highlight some key differences between futures/forwards on financials and on commidities. These are?
Storage costs
Carry markets
Lease rate
convenience yield
define a carry market
A carry market is one where the forward price compensates the commodity owner for storage costs.
two terms on the forward curves
Contango, Backwardation
classify commidities in two broad categories
extractive and renewable
give the formula for the prepaid forward price for a commidity
similar as for financial forwards:
F^P_{0,T} = E[S_T] e^(-aT)
note that we discount ising alpha.
Relate the prepaid forward price of a commidity to the forward price
As alwayss, the forward price is the future value of the prepaid forward price:
F_{0,T} = e^(rT) F^P_{0,T}
F_{0,T} = e^(rT)e^(-aT)E[S_T]
F_{0,T} = E[S_T] e^((r-a)T)
or alternatively:
F_{0,T} = E[S_T] e^(-(a-r)T)
So, the forward price is equal to the expected value of the actual future spot price multuplued the by net effect of the risk free return advantage we have vs the discount effect.
elaborate on the equilibrium condition for commodities like copper, and relate it to stocks
The equilibrium condition for copper is primarily based on extraction costs, not storage costs. This is because the copper is stored safely in the ground. we can extract it if we need it.
Stock on the other hand, has to be stored.
so the thing to understand about commodities like copper is that no one will store them (at least for long periods of time) because this is simply a large storage cost and nothing else.
give the “apparent” arbitrage opportunity on a commidity like copper.
Also give why this is not piossible
Assuming the price is equal to the forward price, we have this case:
Long the forward contract.
Short the underlying.
Invest the shit we get from the short in risk free profit.
At expiration, we would have the amount needed for the contract AND additional risk free rate.
this means that we have earned arbitrage.
This is not possible because of the short sale.
First of all, it is difficult to find copper to short, because very few people will have it available without specific intentions on using it. Therefore, your broker will struggle to find it.
Second, since there is a cost of storage, if we find some assets to short, the lender will require a premium on it, which we refer to as the lease.
elaborate on the lease rate in regards to what is should be
Reference case:
Spot price copper: 3.00
Forward price according to our calculations: 3.30 (just simpel 10%)
Actual forward price: 3.00
The lender of the commodity will identify that we could make arbitrage if his lease is not appropriate. Since we’d make 10% on the price differential when we earn the risk free interest, the lender will take this.
Lease = (1+r)xSpotPrice - F_{0,T}
Lease = 3.30 - 3.00
Lease = 0.3
This payment of 0.30 is the same as the amount that we’d make in profits otherwise.
we can compute the net present value of the investment from the perspective of the lender:
The lender acquire the asset for the current spot price S_0.
Then he gives away. When we receives it back, it will have appreciated in value, and is now worth: E[S_T]. to find the present value of this, we discount using alpha:
E[S_T]e^(-aT)
However, we lend it out and require a lease rate to compensate.
Therefore, we end up with a position that is worth:
E[S_T]e^(-aT)e^(lT), and we finally subtract the spot price we used to purchase the asset:
NPV = E[S_T]e^(-aT)e^(lT) - S_0
We can find the lease rate by setting NPV to 0:
S_0 = E[S_T] e^(-aT)e^(lT)
S_0/E[S_T] = e^(l-a)T
l-a = 1/T ln(S_0/E[S_T])
elaborate on storage costs
Sometimes, storage is not feasible. for instance strawberries, electricity
if you are a commodity merchant, and you have the option of either selling a commodity now or storing it to time T and sell it then, what will you do=
You will store only if the present value of the forward price is at least as great as the spot price today.
when is cash and carry arbitrage NOT profitable