Standard Life's Stakeholder with-profits pension plans were hit by market volatility and lost 1.2% during the first half of the year.
The funds, which do not have investment guarantees, dropped 1.2% over the six months to the end of June (on an estimated gross return basis).
They have the highest equity weighting of Standard Life's with-profits plans at 57.9% at the end of June. The remainder of the funds was in fixed interest and other assets but not property.
Market volatility hit the plans in 2010 after a stronger period in 2009, when they rose just over 19%.
All of Standard Life's other with-profits plans increased in value over the first half of 2010, although with-profits bonds only rose 1.8%. They had an asset split of 43.8% in equities, 39.7% in fixed interest and other assets and 16.5% in property. The highest return over the period was 6% for unitised with-profits life and pension funds.
Standard Life said despite the market volatility, all annual bonus rates on its with-profits plans had been maintained.
Final bonus amounts vary according to the plan and its payment history. They are currently being paid on many unitised with-profits plans but MVRs apply to others.
The average MVR on with-profits bonds is 6.4% but there are currently no MVRs on plans taken out between August 2001 and December 2005, or after October 2008.
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