Attribution Review: Screening Drag, Benchmark Switch and Purification
An Islamic equity fund returned 7.4% over 12 months versus 9.2% for its stated benchmark, the Dow Jones Islamic Market World Index. The manager's marketing note says the 180 bp shortfall is 'purely due to Shariah screening'. Attribution shows: sector allocation effect -2.10% (financials excluded; financials rallied 18%), stock selection +1.15%, currency -0.25%, cash drag -0.40%, purification -0.35%, fees -0.25%. The fund also held 4.5% in a sukuk that was downgraded mid-year, and 2.8% in a private placement valued by a single broker quote. The benchmark returned 9.2%; a Shariah-compliant peer group median was 8.1%. The client asks why the fund underperformed and whether the benchmark is appropriate. The manager wants to switch to a peer-group benchmark and remove purification from performance reporting.
1. Evaluate the manager's claim that the 180 bp shortfall is 'purely due to Shariah screening'.
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The claim is not supported by the attribution. Sector allocation, including the exclusion of financials, contributed -2.10%, which is the largest single effect, but it is not the whole shortfall. Stock selection added +1.15%, currency cost -0.25%, cash drag -0.40%, purification -0.35%, and fees -0.25%. Those items roughly sum to -2.20%, with interactions and residual effects explaining the difference from the reported -1.80%. Purification accounts for only 0.35%, so it cannot be described as the main cause, and screening is not 'pure' because stock selection, currency, cash and fees also affected results. The sukuk downgrade and the private placement valuation may have added further drag not fully captured in the listed attribution. The manager should present a reconciled attribution, separate policy effects from implementation effects, and explain that Shariah screening imposes opportunity costs but not a single deterministic 180 bp penalty. The marketing note should be corrected.
2. Is the Dow Jones Islamic Market World Index an appropriate benchmark? What should be disclosed if the manager switches to a peer-group benchmark?
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The Dow Jones Islamic Market World Index is an appropriate primary benchmark because it is a Shariah-compliant, rules-based, investable universe that matches the fund's mandate. The peer group median of 8.1% is a useful secondary reference, but peer groups differ in asset allocation, credit quality, liquidity and Shariah methodology, so they are not a clean replacement. Switching to a peer-group benchmark after a period of underperformance raises a benchmark-shopping concern. If the manager switches, it should disclose the change with a clear rationale, show the old and new benchmarks side by side for prior periods, explain that the peer group is a secondary comparator rather than a policy benchmark, and obtain client or governance approval. The manager should also disclose the peer group's composition and dispersion, not just the median. The primary benchmark should remain the Shariah-compliant market index unless the client's mandate specifically calls for a peer-relative objective.
3. How should purification and the sukuk downgrade be treated in performance and client reporting?
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Purification is a real cost of Shariah compliance and should be reported separately, not removed. The fund should show gross return, purification, fees, and net return, with a reconciliation to the benchmark. Removing purification would overstate performance and obscure the cost of non-compliant income. The 0.35% purification should be disclosed by holding and by methodology so the client can see how it was calculated. The sukuk downgrade should be treated as a valuation and credit event: mark the position to market, disclose the downgrade date, the price effect, and any change in credit risk, and explain whether the fund still holds the sukuk and why. The private placement valued by a single broker quote should be flagged as a valuation risk, with an independent price or a valuation committee review. The client report should include a clear performance bridge from benchmark to fund, separating sector exclusion, stock selection, currency, cash, purification, fees, and one-off credit and valuation effects.