Australia’s mining boom should maintain its strength throughout this fiscal year, economists say.

Official data released on Thursday showed that new private capital expenditure rose 2.8 per cent in real terms, seasonally adjusted, in the September quarter.

The median market forecast was for a 2.0 per cent rise.

The fourth estimate of expenditure for 2012/13 is $173.350 billion, not adjusted for inflation, which is 3.3 per cent lower than the third estimate for 2012/13.

It is 4.9 per cent higher than the fourth estimate for 2011/12.

St George economist Janu Chan said the data was positive for the resource sector in the near term.

“It hasn’t changed our view of what’s happening with investment,” she said.

“The plans suggest that mining capex is still going to be sizeable for the 2012/13 period.

“Unfortunately, we don’t get the plans for 2013/2014 as yet. That’s the number that will really tell us when the mining boom will peak.”

Ms Chan said the data would be unlikely to stop the Reserve Bank of Australia (RBA) from cutting the cash rate from 3.25 per cent when it meets on Tuesday.

Commonwealth Bank associate economist Diana Mousina said the Capex data was positive for the September quarter, but the drop in spending estimates for 2012/13 would be a concern for the RBA.

She said the figures could add to concerns about a rocky transition phase for the Australian economy once the boom in mining investment peaks.

“I guess it shows that spending intentions are not as high as they have been in the past because of project cancellations and deferrals,” she said.

“So that is definitely a risk once the mining boom passes through.”

Ms Mousina expected the RBA to cut rates either in December or in February.

“It is probably a 50/50 chance of a cut in December and if they don’t cut next month we’re expecting a cut in February.”

The RBA board does not meet in January.