Oasis Asset Management retained its position as the top collective investment scheme manager when all the managers were ranked on the average PlexCrowns they earned in various unit trust categories over different periods to the end of September 2006.
The PlexCrown rating system uses four different measures of performance and risk to determine an overall rating between one and five - with five being the highest rating.
The top manager is determined by averaging the PlexCrowns of each manager's funds in each unit trust sub-category, with an emphasis on the manager's domestic funds.
According to Ryk de Klerk, who developed the PlexCrown ratings for Plexus Research and Surveys, Oasis achieved a weighted average of 4.666 PlexCrowns, while Coronation maintained its second place overall with 3.958 PlexCrowns.
Investec finished third with a weighted average of 3.533, with Prudential (3.375) and RMB (3.333) hot on its heels, while Nedgroup dropped to sixth spot in the third quarter of this year.
Oasis was placed first when the managers were ranked on the PlexCrown performance of all their domestic funds, De Klerk says.
It was second, after Frater Asset Management, in the rankings for domestic equity funds and joint second with Nedgroup and Community Growth in the rankings for domestic fixed-interest funds. Coronation was first in the rankings for domestic fixed-interest funds.
In the domestic asset allocation rankings, Oasis was in first place together with Allan Gray, RE:CM and Fraters. Oasis was first in the domestic real estate category and first in the sub-category for foreign general equity funds.
De Klerk says Oasis was also the investment house to produce the most improved PlexCrown ratings since the end of last year, followed by RMB and Prudential.
Among the managers who did not qualify for an overall or a regional rating, Fraters continued to lead the domestic equity ranking and shared the top spot in the domestic asset allocation rankings.
When the collective investment managers' abilities to manage different types of assets were analysed, De Klerk found Oasis was the best-rated manager in both the domestic equity and fixed-interest sub- categories, followed by Coronation, Investec and Nedgroup.
Despite the fact that Oasis had the highest average PlexCrown score when management companies were ranked on their foreign funds, it did not have any foreign fixed- interest funds.
As a result, De Klerk says, Old Mutual and Prudential were the most proficient at managing foreign investments when their abilities to manage foreign equity and fixed-interest funds were considered. Prudential was also the best manager of both domestic and foreign fixed-interest funds, he says.
Coronation, Absa and Momentum had the highest ratings in both the foreign and domestic asset allocation sub-categories.
Oasis was the best manager of both domestic and foreign equity funds, and was the best manager overall across all the domestic and foreign categories, followed by Coronation.
The four different measures used to determine the PlexCrown fund ratings are: the Sortino ratios, which measure a fund's performance against the risk of under-performing a benchmark; the Sharpe ratios, which measure a fund's deviation (up or down) from its benchmark; alpha, which measures the return a fund earned over and above the market in which it operates; and the Morningstar raw ratings, which measure the average excess of return of the fund.
Once the PlexCrown ratings have been determined for each unit trust fund, the average rating each manager achieves for all its funds in each of the domestic unit trust sectors of asset allocation, equity and fixed interest are calculated. These averages are then given equal weights in determining an overall domestic fund average.
In order to qualify for a domestic rating, the unit trust manager must have a fund listed in each of the above-mentioned sectors.
A manager's foreign rating is calculated by averaging the ratings of all the manager's funds listed in the foreign sectors. A manager has to have at least one fund listed in the foreign equity general sub-category to qualify for a foreign rating.
The overall rating of unit trust managers is calculated by applying weights of 75 percent and 25 percent to the domestic and foreign ratings respectively. A manager must have a domestic and foreign rating to qualify for an overall rating.