Impaired debt buyer and lender Credit Corp was not able to capitalise on strong revenue growth in the six months to December, with higher marketing costs and consumer loan loss provisions eating into the bottom line.Credit Corp reported revenue of A$112.2 million for the six months to December - an increase of 19.8 per cent over the previous corresponding period.However, profit rose only 5.5 per cent to $21.2 million and earnings per share rose 4.8 per cent. A number of expense items rose but marketing and loan loss provisions were the main culprits.Debt ledger purchasing is the company's biggest business. Revenue rose 10.7 per cent to $86 million, compared with the previous corresponding period, and EBITDA rose 12.2 per cent to $30.4 million.Highlights for the business during the half included recorded debt purchases worth $98.5 million, and five per cent growth in the proportion of its book operating under recurring payment arrangements.The number of accounts under payment arrangements rose from 125,000 to 139,000 over the 12 months to December and the face value of those accounts rose from $963 million to $1.1 billion.Credit Corp's other division, consumer lending, was more volatile. Revenue grew by 57.6 per cent to $26.2 billion but EBITDA fell 29.4 per cent to $2 million.The company said in its review of operations that the rapid growth in the loan book (net lending was $32 million during the half) affected earnings because its policy was to provision for loan losses upfront. It said customer acquisition costs were also higher.It said more modest growth in the second half would improve the division's bottom line.In October Credit Corp announced that it was getting out of the small amount credit contract end of the market and would focus larger loans with longer terms.