SCT08183658301-94

Table A: [Confidence limits] 95% confidence limits for estimates, based on SHS sub-samples sizes
Sub-sample size (=100%) Estimate
5% 10% 15% 20% 25% 30% 35% 40% 45%
or or or or or or or or or  
95% 90% 85% 80% 75% 70% 65% 60% 55% 50%
percentage points  ( + / - )
100 5.0 6.8 8.1 9.1 9.8 10.4 10.8 11.1 11.3 11.4
200 3.5 4.8 5.7 6.4 7.0 7.4 7.7 7.9 8.0 8.0
300 2.9 3.9 4.7 5.3 5.7 6.0 6.3 6.4 6.5 6.6
400 2.5 3.4 4.1 4.5 4.9 5.2 5.4 5.6 5.7 5.7
500 2.2 3.1 3.6 4.1 4.4 4.7 4.8 5.0 5.1 5.1
600 2.0 2.8 3.3 3.7 4.0 4.3 4.4 4.5 4.6 4.6
700 1.9 2.6 3.1 3.4 3.7 3.9 4.1 4.2 4.3 4.3
800 1.8 2.4 2.9 3.2 3.5 3.7 3.8 3.9 4.0 4.0
900 1.7 2.3 2.7 3.0 3.3 3.5 3.6 3.7 3.8 3.8
1,000 1.6 2.2 2.6 2.9 3.1 3.3 3.4 3.5 3.6 3.6
1,200 1.4 2.0 2.3 2.6 2.8 3.0 3.1 3.2 3.3 3.3
1,400 1.3 1.8 2.2 2.4 2.6 2.8 2.9 3.0 3.0 3.0
1,600 1.2 1.7 2.0 2.3 2.5 2.6 2.7 2.8 2.8 2.8
1,800 1.2 1.6 1.9 2.1 2.3 2.5 2.6 2.6 2.7 2.7
2,000 1.1 1.5 1.8 2.0 2.2 2.3 2.4 2.5 2.5 2.5
2,500 1.0 1.4 1.6 1.8 2.0 2.1 2.2 2.2 2.3 2.3
3,000 0.9 1.2 1.5 1.7 1.8 1.9 2.0 2.0 2.1 2.1
3,500 0.8 1.2 1.4 1.5 1.7 1.8 1.8 1.9 1.9 1.9
4,000 0.8 1.1 1.3 1.4 1.6 1.6 1.7 1.8 1.8 1.8
5,000 0.7 1.0 1.1 1.3 1.4 1.5 1.5 1.6 1.6 1.6
6,000 0.6 0.9 1.0 1.2 1.3 1.3 1.4 1.4 1.5 1.5
7,000 0.6 0.8 1.0 1.1 1.2 1.2 1.3 1.3 1.4 1.4
8,000 0.6 0.8 0.9 1.0 1.1 1.2 1.2 1.2 1.3 1.3
9,000 0.5 0.7 0.9 1.0 1.0 1.1 1.1 1.2 1.2 1.2
10,000 0.5 0.7 0.8 0.9 1.0 1.0 1.1 1.1 1.1 1.1
12,000 0.5 0.6 0.7 0.8 0.9 1.0 1.0 1.0 1.0 1.0
14,000 0.4 0.6 0.7 0.8 0.8 0.9 0.9 0.9 1.0 1.0
16,000 0.4 0.5 0.6 0.7 0.8 0.8 0.9 0.9 0.9 0.9
18,000 0.4 0.5 0.6 0.7 0.7 0.8 0.8 0.8 0.8 0.8
20,000 0.4 0.5 0.6 0.6 0.7 0.7 0.8 0.8 0.8 0.8
25,000 0.3 0.4 0.5 0.6 0.6 0.7 0.7 0.7 0.7 0.7
30,000 0.3 0.4 0.5 0.5 0.6 0.6 0.6 0.6 0.7 0.7
35,000 0.3 0.4 0.4 0.5 0.5 0.6 0.6 0.6 0.6 0.6
40,000 0.2 0.3 0.4 0.5 0.5 0.5 0.5 0.6 0.6 0.6
45,000 0.2 0.3 0.4 0.4 0.5 0.5 0.5 0.5 0.5 0.5
50,000 0.2 0.3 0.4 0.4 0.4 0.5 0.5 0.5 0.5 0.5

e.g. an estimate of 55% that is based on a sample of 800 has 95% confidence limits of 55% ± 4.1% points
2013 Design factor = 1.16
Formula used is CI = 1.16 x 1.96 x SQRT((% x (1-%)) / n )