IN THE MIDST of the controversy surrounding a near five million tonne discrepancy in the size of the national 2016-17 wheat crop between two government agencies the Australian Bureau of Statistics (ABS) has said it is normal for estimates to vary.
The ABS has come up with a preliminary figure for the 16-17 wheat crop of 30.35 million tonnes, compared to national grain forecaster ABARES, which issued a figure of 35m tonnes.
This divergence has raised eyebrows in the grain industry, with farmer groups saying opaque stocks reporting meant it was difficult for the market to gauge accurately how much grain is around and set a fair price.
Some farmers have openly said they do not cooperate with bodies seeking to collate information on grain stocks, saying they feel it will be used by the grain buyers against them.
This is an especially big problem for the ABS, which works primarily off information provided by growers.
Kirrilie Horswill, of the ABS, said data for the ABS estimates came through a survey of Australian farm businesses.
She said the estimates would always vary, not only from ABARES but from the numbers put out by private forecasters.
“The ABS estimates are based on a survey of producers / farm businesses meeting certain criteria and on the goodwill and cooperation of our respondents,” Ms Horswill said.
However, Rankin Springs, NSW, farmer and grains industry activist Jock Munro highlighted the fact not all growers were willing sharers of information.
“I don’t provide information to the industry as I feel any information that can be used by the merchants will not be used in growers’ interests,” Mr Munro said.
He said he felt there should be greater disclosure in terms of stocks information provided by the leading bulk handlers.
“We’ve seen with what has happened with this issue with the 16-17 wheat crop, there’s no doubt growers lost out as the marketers played on the idea there was a heap more wheat out there and prices fell accordingly.”
Ms Horswill acknowledged there were limitations to the methodology used by ABS.
“Not everyone responds in a timely way (or at all) and we adjust for this as well as weighting up for farm businesses that we haven’t included in sample,” she said.
She said this meant there were usually changes between the preliminary and final estimates.
“We have more information available to produce our final estimates than preliminary estimates due to more responses being in.”
Along with the estimates, Ms Horswill said other information, such as receival data, exports, crop reports, rainfall and temperature reports were consulted, but she said the final figures were predominately driven by the survey responses.
In terms of methods used to create an estimate, Ms Horswill stressed there were differences in conducting crop forecasting, which is ABARES’ primary focus, compared to coming up with a post-harvest estimate.
“There are quite different methodologies behind crop forecasting models which are looking ahead, rather than backward and based on expected outcomes.”
For wheat, she said participating farm businesses were asked for estimates of their production and area grown and total base estimates were made off these responses.