UI = sqrt(sum[i=1,2,...,n](D'_i^2/n)) where
D'_i = drawdown since previous peak in period i
DETAILS:
This approach is sensitive to the frequency of the time periods involved
and penalizes managers that take time to recover to previous highs.
REFERENCES:
Martin, P. and McCann, B. (1989) The investor's Guide to Fidelity Funds:
Winning Strategies for Mutual Fund Investors. John Wiley & Sons, Inc.
See also package PerformanceAnalytics
.