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If this is a failed pension plan that was picked up by The Pension Benefit Guaranty Corporation and I lost 90% of the value promised by my now bankrupted employer, how do I factor the amount I contributed?  If I'm only receiving 10 cents on the dollar promised, how to do factor taxable amount?  Or do I plan it safe and assume its all taxable and give Uncle Sam 3 cents of the 10 cents?