Company profits continued to rise solidly in the September quarter, and the weaker exchange rate is starting to help.

Company gross operating profits rose 3.9 per cent in the September quarter and were up 8.9 per cent in the 12 months to September, the Australian Bureau of Statistics (ABS) said on Monday.

Commonwealth Bank economist Diana Mousina said the falling Australian dollar was boosting profits for exporters.

A falling Australian dollar makes exports more competitive and imported goods dearer.

“Despite the doom and gloom reported about the mining and manufacturing sectors, both recorded the strongest increase in profits in the third quarter,” Ms Mousina said.

“Given the sensitivity of both industries to a lower currency, the 10 per cent depreciation in the Aussie dollar in the June quarter would have assisted significantly.

“The expected decline in the currency over 2014 will be positive for company profit earnings.”

However there is a risk that a small fall in inventories – materials, unfinished goods and unsold stock – could weigh on the official economic growth figures to be released on Wednesday.

Estimated business inventories fell 0.5 per cent in the September quarter, seasonally adjusted, following a 0.4 per cent rise in the three months to June.

JP Morgan economist Tom Kennedy said mining inventories have increased in the past two quarters as more and more of the output is being stockpiled and not exported.

“Whether this is a supply-side or demand-side constraint is open to debate, although we lean toward the former,” he said.

“In contrast, company profits were considerably firmer than the market had anticipated buoyed by the expected deceleration in wage and salary growth.

“These contrasting factors should essentially cancel one another out in this week’s GDP (gross domestic product) data; we still forecast growth at 0.7 per cent, quarter on quarter.