Submitted by cahn on 21 June, 2009 - 5:07pm
Perpetual Tracker with Risk Target ("Perpetual+") is an investment process with the following objectives:
- Manage the portfolio with a fixed risk target (risk target being defined as the realised volatility)
- Ensure a certain percentage of the highest reached portfolio value is protected on a perpetual basis
The process is a version of the Time-Invariant Portfolio Insurance ("TIPI") technique and defines the Multiplier (a measure of riskiness of the portfolio) as a function of the realised volatility of the portfolio, reflecting the view that the riskiness of an underlying is not constant.
I have been running a process since 19 May 09 on Hang Seng China Enterprises Index ("HSCEI"). The process switches between the index and the overnight money market depending on
- The distance between the portfolio and the targeted protection
- The 30-day realised volatility of the index
Below are the specification of the process:
- Protection ("BF"): 70% of the highest reached portfolio value ("RPV")
- Multipler: Min(8, 8 x Vol Target / 30-day Realised Volatility)
- Vol Target: 15%
- Rebalance Tolerance: +/-10%
- Maximum exposure to HSCEI: 240%
- Minimum exposure to HSCEI: 0%
- Initial portfolio value: $500,000

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dS_t^{a}=\mu_{a}S_t^{a}dt+\sqrt{\sigma_{s}^2+\sigma_{fx_{h}fx_{a}}^2+2\sigma_{s}\sigma_{fx_{h}fx_{a}}\rho_{s,fx_{h}fx_{a}}}S_t^{a}d\acute{W}_t\]](/portal/files/tex/ad5316854c40ab26e1a21d872760c09eb262754b.png)