Macquarie Group's lending and leasing division, Corporate and Asset Finance, lost ground in the six months to September. Income was down four per cent on the previous corresponding period and the net profit contribution was down six per cent.Corporate and Asset Finance, which is the second biggest contributor to group earnings, has been a mainstay for Macquarie since the global financial crisis.Macquarie Group's chief executive, Nicholas Moore, said the weaker result was due to a couple of one-off items. The aircraft leasing business "ran down a little" and there was a high level of corporate loan prepayments.As a result of aircraft sales, the value of the aircraft leasing portfolio was down 13 per cent on the previous corresponding period, to A$3.2 billion.Moore said: "The overall portfolio has been maintained, with $1.4 billion of new business coming in."Corporate and Asset Finance net operating income was down, from $528 million in the September half last year to $507 million in the latest half. Profit was down from $358 million to $335 million over the same period.The impairment charge of $19 million was in line with the previous corresponding period, and was down from a charge of $44 million for the March half.Moore said the outlook for the division for the full year, ending March 31, was broadly in line with the 2011/12 result.He said the division was expanding its mining equipment finance business, which was a small part of its operation and represented a good growth opportunity.Other expansion activities included the purchase of a railway leasing portfolio in November last year and the purchase of OnStream, a United Kingdom meters business, in October last year.At September 30, the division had $21.4 billion of loans and assets under finance.