APPENDIX 1 - EXPECTATIONS DATA
Adjustments to expectations data
The ABS proposes to change the methodology used to compile the expected expenditure on mineral exploration series presented in Table 1 of this publication.
From June quarter 2000, an adjustment was applied to the expectations for each period so that the expectations data would be a more reliable indicator of expenditure for the period. These adjustments were applied to the time series back to the December half 1989 in order to present the full time series on a consistent basis. The June quarter 2000 issue of this publication contains details of how these adjustments were derived.
Subsequent investigations have shown that these adjustments have not been successful in creating a reliable expectations series. For expectations to be a reliable predictor, the most important feature is their consistency over time in terms of their relationship with actual expenditure (the "realisation ratio"). For example, if a particular expectations series consistently understates actual expenditure by 30% over time, then the expectations data is a useful predictor of the actual outcome. In the case of the mineral exploration expectations series, the adjustments have not removed the volatility in these realisation ratios to any great degree, although they have removed the downward bias in the unadjusted series.
From next quarter's release, the ABS intends to present the expectations data and consequent realisation ratios in their unadjusted forms. These data will be available for the full time series. Information on average realisation ratios will also be provided. The adjusted expectation series will be retained to assist users in making their assessments of the likely expenditure for the periods covered by the expectations data.
The table below presents the actual expenditure, expectations as collected and the adjusted expectations through the time series from December 1989, as well as the adjustment factors which had been applied to the expectations previously released and comparative realisation ratios.
MINERAL EXPLORATION: COMPARISON OF UNADJUSTED AND ADJUSTED EXPECTED EXPENDITURE |
|
| | | | | Actual as a | Actual as a |
| | | | Adjustment | proportion of | proportion of |
| | Unadjusted | Adjusted | factor | unadjusted | adjusted |
| Actual | expected | expected | applied | expected | expected |
| | | | | | |
Half Year | $m | $m | $m | % | % | % |
|
|
Dec 1989 | 316.0 | 270.7 | 376.3 | 1.390100 | 116.7 | 84.0 |
Jun 1990 | 291.6 | 268.3 | 309.0 | 1.151696 | 108.7 | 94.4 |
Dec 1990 | 310.5 | 228.4 | 336.4 | 1.472855 | 135.9 | 92.3 |
Jun 1991 | 291.1 | 224.2 | 252.3 | 1.125335 | 129.8 | 115.4 |
Dec 1991 | 317.7 | 222.3 | 330.7 | 1.487629 | 142.9 | 96.1 |
Jun 1992 | 286.3 | 244.3 | 278.2 | 1.138764 | 117.2 | 102.9 |
Dec 1992 | 335.5 | 257.0 | 363.4 | 1.414008 | 130.5 | 92.3 |
Jun 1993 | 296.3 | 275.8 | 318.7 | 1.155547 | 107.4 | 93.0 |
Dec 1993 | 396.4 | 223.6 | 331.9 | 1.484347 | 177.3 | 119.4 |
Jun 1994 | 396.2 | 319.4 | 374.8 | 1.173450 | 124.0 | 105.7 |
Dec 1994 | 458.4 | 349.2 | 450.4 | 1.289805 | 131.3 | 101.8 |
Jun 1995 | 443.0 | 428.7 | 515.4 | 1.202239 | 103.3 | 86.0 |
Dec 1995 | 456.5 | 372.3 | 472.2 | 1.268332 | 122.6 | 96.7 |
Jun 1996 | 503.8 | 401.3 | 480.2 | 1.196611 | 125.5 | 104.9 |
Dec 1996 | 565.7 | 361.8 | 462.3 | 1.277778 | 156.4 | 122.4 |
Jun 1997 | 582.8 | 447.1 | 539.1 | 1.205771 | 130.4 | 108.1 |
Dec 1997 | 583.8 | 513.7 | 605.7 | 1.179093 | 113.6 | 96.4 |
Jun 1998 | 483.1 | 387.6 | 462.5 | 1.193240 | 124.6 | 104.5 |
Dec 1998 | 475.2 | 299.2 | 403.3 | 1.347928 | 158.8 | 117.8 |
Jun 1999 | 362.3 | 303.4 | 354.2 | 1.167436 | 119.4 | 102.3 |
Dec 1999 | 356.9 | 252.8 | 359.5 | 1.422073 | 141.2 | 99.3 |
Jun 2000 | 319.4 | 284.8 | 330.3 | 1.159761 | 112.1 | 96.7 |
Dec 2000 | 357.0 | 245.6 | 352.7 | 1.436075 | 145.4 | 101.2 |
Jun 2001 | 326.3 | 272.7 | 314.7 | 1.154015 | 119.7 | 103.7 |
Dec 2001 | 338.1 | 320.1 | 423.0 | 1.321462 | 105.6 | 79.9 |
Jun 2002 | 302.7 | 258.7 | 296.7 | 1.146888 | 117.0 | 102.0 |
Dec 2002 | 375.7 | 311.4 | 414.7 | 1.331728 | 118.0 | 103.0 |
Jun 2003 | n.y.a. | 285.9 | 331.7 | 1.160196 | n.y.a. | n.y.a. |
|
Survey procedures
The main deficiencies in these unadjusted expectations result from the inability of some businesses to accurately predict their expenditure for the following six months. The ABS is intending to modify the procedures used in the quality assurance process for these expectations, including imputation for missing data, over coming quarters. This is expected to increase the usefulness of these expectations as a predictor of actual expenditure. Information will be included in the release which quantifies the quality improvements that arise from the change in survey procedures so that estimates compiled on the old and new basis are comparable.
Expectations for petroleum exploration are unaffected by this change. These data have previously been compiled by aggregating the reported expectations data without adjustment and this will continue to be the case.
Please contact John Blanchette on 02 9268 4429 or by email john.blanchette@abs.gov.au for more information.