Business confidence and job advertising weakened in April, signalling that a rapid increase in interest rates is now starting to cool the economy. Business confidence levels fell for the second consecutive month in April as sentiment across the retail, building and transport sectors soured, according to a survey by the National Australia Bank. NAB's monthly business survey found confidence in April fell 3 points to an index reading of plus 13, still above the long-run average of plus 7. Business conditions fell 5 points to plus 8, NAB said.