This temporary realignment of portfolio beta and duration in response to changing market
values or to our view of the market is the province of tactical asset allocation. Since
shifts of portfolio betas are much more common than shifts of portfolio duration, we
shall, in this chapter, focus on beta shifts. But many of the same principles apply to shifts
of duration also.
Market Timing
It is obvious that switching to offensive and defensive portfolio according to our view of
the market trends is subject to a great deal of risk. If the market moves down when we
are holding an offensive portfolio because we expected the market to rise, we stand to
lose heavily. This is because an offensive portfolio drops even more rapidly than the
market. Similarly, if the market rises while we are holding a defensive portfolio in the
expectation of a slump in prices, we suffer an opportunity loss. A defensive portfolio
does not rise as fast as the market does and we lose out on the gains that we could have
made. This means that the switching of portfolio beta must be done with great care.
How far we are willing to go in moving away from our target beta depends on the degree
of confidence that we have in our forecast of market trends. Unless we are very
confident about our forecasts, we would be well advised to stick to our target beta.
From a practical point of view, the important question is how we implement the
temporary shifts in the portfolio betas. For example, suppose we want to temporarily
adopt a defensive portfolio (with say a beta of 0.6) with the intension of reverting to our
target beta (of say 1.1) in the near future. What options do we have? We could consider
the following possibilities:
- Switch a part of the portfolio to bonds (debentures), i.e. sell a part of our
equity portfolio and invest the proceeds in debentures. - Switch a part of the portfolio to money market instruments. This could
include the unorganized money market; for many brokers, it is more
convenient to invest excess funds in the badla finance market. Of course,
the risks involved in operating in the unorganized market are quite
different from that involved in the organized markets. - Reduce the average beta of the equity portfolio by selling high beta stocks
and buying low beta stocks. - Short sell high beta stocks.
All the above do succeed in creating a defensive portfolio and can be regarded as
equivalent in this sense. But in practice, there are important differences in these options:
- Transaction costs (brokerage, etc.) are different in these alternative routes:
these costs are typically lower in the forward market.