If Barclays hasn't, in fact, obtained or offered such loans, its new rules say it must calculate the rate on the basis of other secured loans that the bank has been involved with (i.e. loans backed by collateral).

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Overexposure to construction and development loans including loans secured by multifamily and commercial properties: If loans for construction, land development, and other land, and loans secured by multifamily and commercial property are 300% or more of total risk capital, the institution would also be considered to have a CRE concentrations above prudent levels, and should employ heightened risk management practices.

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The figures help explain why interest rates are so much higher on credit cards, and other forms of unsecured loans, than on mortgages which are secured on borrowers' property.

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Late payment also rose on other types of borrowing, such as car loans and lines of credit secured on owned homes.

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