The slide will fuel worries that official job data on Thursday would show a further rise in unemployment, which is already at a four-year high of 5.2 per cent.
The survey from Australia and New Zealand Banking Corp showed the total number of job advertisements fell 8.5 per cent in March from the month before, to average 147,804 a week.
That was the 11th straight monthly drop and brought the fall since March last year to a huge 44.6 per cent, the biggest annual decrease on record.
'Sharply falling ANZ job ads is consistent with an extended period of labour market weakness that is likely to see the unemployment rate heading higher throughout 2009 and 2010,' said said Warren Hogan, ANZ's head of Australian economics.
ANZ now expects the jobless rate to top 8 per cent in 2010 and the economy as a whole to contract by 1 percent this year.
The grim reading will add to pressure on the Reserve Bank of Australia (RBA) to cut interest rates again at its monthly policy meeting on Tuesday. The central bank skipped an easing in March having already slashed its key cash rate by 400 basis points to a record low of 3.25 per cent in the previous six months.
Analysts expect the official labour report to show the jobless rate rose to 5.4 per cent in March, the highest in over four years, from 5.2 per cent in February and a trough of 3.9 per cent in February last year.
Monday's survey showed the number of job advertisements in major metropolitan newspapers fell 6.6 per cent in March, to average 7,958 per week. That was a drop of 53.4 per cent compared to March last year.
Advertising on the Internet dropped by 8.6 per cent, on top of a 9.4 per cent decline in February, to average 139,846. That was 44 per cent lower than the same month last year. -- THOMSON REUTERS
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