Credit unions had their best quarter for housing loan growth in four years during the December 2007 quarter. But the sector is not growing nearly so quickly on the liability side of its balance sheet, and in the current climate the latter trend is likely to prove a brake on growth.Quarterly data on the credit union sector published by the Australian Prudential Regulation Authority late last week shows that credit unions recorded growth of 3.4 per cent in housing loan assets in the three months to December 2007.With annnualised growth of 13 per cent over the quarter the sector has thus had slightly better than system growth in the home loan segment for this period. The sector has otherwise lagged market growth in most quarters over the last four years.It's doubtful credit unions will maintain this lending growth, however.The APRA data shows growth of 2.9 per cent in deposits over the December quarter, with growth of 1.96 per cent in at-call deposits.By comparison banks recorded growth in business deposits of 10 per cent during the December quarter and growth in household deposits of four per cent during the quarter.