Forecast Accuracy and Uncertainty of Australian Bureau of Statistics State and Territory Population Projections
Table 2
Selected error statistics for ABS state and territory projections of total population by projection duration.
Projection duration (years)
NSW
Vic
Qld
SA
WA
Tas
NT
ACT
MedAPE (%)
0
0.06
0.11
0.20
0.11
0.17
0.11
0.95
0.23
5
0.65
0.83
2.20
0.96
2.56
0.72
3.45
2.66
10
0.77
3.11
2.92
2.87
2.38
1.17
6.38
5.83
15
1.56
2.43
4.45
3.40
4.77
2.56
9.47
8.15
MedPE* (%)
0
0.00
0.02
0.06
0.04
0.00
−0.11
−0.95
0.00
5
0.12
−0.52
−0.53
0.30
0.58
−0.28
−1.44
−0.24
10
−0.08
−1.21
−2.50
0.28
−0.30
0.57
1.92
4.78
15
−0.15
0.56
−4.45
0.53
−1.32
2.08
9.34
7.59
Upper bound of middle 80% of APE values (%)
0
0.18
0.55
0.52
0.41
0.78
0.54
2.44
0.82
5
1.39
2.21
3.02
2.00
5.29
3.36
6.72
5.02
10
2.64
5.28
6.50
4.29
7.90
5.62
11.15
8.57
15
3.79
6.76
7.92
4.04
10.98
4.90
17.47
13.15
Lower bound of middle 80% of APE values (%)
0
0.00
0.01
0.00
0.03
0.00
0.01
0.00
0.07
5
0.40
0.37
0.39
0.39
0.97
0.28
0.17
0.60
10
0.11
0.59
0.63
0.84
1.01
0.23
0.96
1.30
15
0.15
0.42
1.26
0.92
1.89
1.36
3.06
3.47
Width of 80% interval of APE (%)
0
0.18
0.54
0.52
0.38
0.78
0.54
2.44
0.75
5
0.99
1.84
2.62
1.60
4.31
3.08
6.54
4.42
10
2.53
4.68
5.87
3.45
6.89
5.39
10.19
7.28
15
3.64
6.34
6.66
3.12
9.09
3.54
14.41
9.68
Source: author’s calculations using ABS projections and ERP data.
*Negative values of MedPE indicate projections which were too low on average; positive values indicate projections which were too high.
