Demand for fixed-rate mortgages has plummeted over the past few months, as borrowers anticipate further cuts in interest rates.The Reserve Bank cut the official cash rate by 25 basis points in October and by 25 points in December. A number of bank economists are predicting there will be more cuts this year.Mortgage aggregator AFG reported yesterday that the share of fixed-rate business being written by its loan writers has fallen from 21.5 per cent in September to 16.3 per cent in January. Broker Mortgage Choice reported that fixed-rate loans made up more than 20 per cent of its business through 2012 but fell to 16.3 per cent in January.Mortgage Choice's spokesperson, Belinda Williamson, said in a statement: "There is now also the possibility of out-of-cycle variable rate cuts, thanks to recent news of eased funding costs."AFG reported A$2.3 billion worth of mortgage sales in January. Business was down on previous months, but January is usually a weak month for home-loan sales and the result was 24 per cent up on January last year.