 The major factors for the changes in operating lease, rental and other income, depreciation and other expense and lease  margin for the year ended December 31, 2011 are outlined in the table below: OPERATING LEASE, RENTAL  DEPRECIATION  LEASE  ($ in millions) AND OTHER INCOME  AND OTHER  MARGIN 2010 $546.2  $451.6  $ 94.6 Increase (decrease) Operating lease impairments (3.8) 3.8 Results on returned lease assets  (19.5) 19.5 Average operating lease assets  34.3 27.8 6.5 Revenue and cost per asset  21.8 17.6 4.2 Currency translation and other  3.9 2.5 1.4 Total increase  60.0 24.6 35.4 2011 $606.2  $476.2  $130.0 •   The decrease in operating lease impairments and improved results on trucks returned from leases in 2011 reflect  higher used truck prices.  •   Average operating lease assets increased $214.3 million in 2011, which increased income by $34.3 million and  related depreciation on operating leases by $27.8 million, as a result of higher volume of equipment placed in  service reflecting higher demand for leased vehicles.  •   Higher truck transportation demand also resulted in an increase in revenues per asset in 2011. The increase in  revenue consisted of higher asset utilization (the proportion of available operating lease units that are being leased)  of $4.4 million, higher lease rates of $13.5 million and higher fuel and service revenue of $3.9 million. The 2011  increase in costs per asset of $17.6 million is due to higher vehicle operating expenses, including higher fuel costs  and variable costs from higher asset utilization levels.  The following table summarizes the provision for losses on receivables and net charge-offs: The provision for losses on receivables for 2011 declined $19.6 million compared to 2010 due to generally improving  economic conditions which have improved the profitability and cash flow for many of the Company’s customers in  the transportation industry, particularly in the U.S. and Canada.  ($ in millions)  2011 2010 PROVISION FOR PROVISION FOR  NET  LOSSES ON NET  LOSSES ON  CHARGE-OFFS RECEIVABLES CHARGE-OFFS   RECEIVABLES U.S. and Canada  $  6.7 $ 3.8 $ 35.7  $ 21.0 Europe   15.3 17.9  27.2  20.9 Mexico and Australia 23.0 19.7 20.4 19.1 $ 45.0 $ 41.4 $ 83.3  $ 61.0 At December 31, 2011  2010 Percentage of retail loan and lease accounts 30+ days past-due: U.S. and Canada  1.1% 2.1% Europe  1.0% 2.5% Mexico and Australia  3.4% 5.8% Total  1.5% 3.0%