COMMONWEALTH BANK CUTS AUSTRALIAN SPLIT PRIME The Commonwealth Bank of Australia said it will lower its reference rate for loans to 15.75 pct from 16.25 pct and its overdraft reference rate to 16.25 pct from 16.75, effective June 24. Bank officials have said the bank regards the overdraft reference rate, based on short-term rate trends, as its key prime lending rate to corporate customers. The loan reference rate is based on longer term trends. The bank is the latest to cut prime rates in recent days following a continuing decline in market rates. Other prime rates now range from 16 pct to 17.5 pct.