Comparison of areas with census data
This report compares the sample characteristics of the oversampled areas of Cockburn, Rockingham and Kwinana with the census characteristics for key socio demographic variables. Each area is examined separately and the results presented as comparisons between the sample and the census information for that area.
The Cockburn sample
Comparison of age and sex with census
This section provides a comparison of the Cockburn sample with the 2001 Census information. All comparisons with Census data are taken from the ABS website1,2 .Cockburn has a population of 66,417 people. As with WA as a whole, Cockburn has marginally more females (50.1%) than males (49.9%). Table 1 presents the age and sex distribution of the Cockburn sample.
Table 1Cockburn sample by age and sex
Age Group / Female / Male / Persons0 to 4 / 28 / 32 / 60
5 to 9 / 23 / 24 / 47
10 to 15 / 35 / 33 / 68
16 to 19 / 37 / 31 / 68
20 to 24 / 33 / 31 / 64
25 to 29 / 27 / 25 / 52
30 to 34 / 40 / 29 / 69
35 to 39 / 31 / 26 / 57
40 to 44 / 37 / 25 / 62
45 to 49 / 34 / 17 / 51
50 to 54 / 42 / 23 / 65
55 to 59 / 37 / 21 / 58
60 to 64 / 34 / 22 / 56
65 to 69 / 19 / 19 / 38
70 to 74 / 28 / 17 / 45
75 to 79 / 17 / 11 / 28
80 to 84 / 9 / 9 / 18
85 & over / 6 / 2 / 8
Total / 517 / 397 / 914
Table 2 indicates that there were more people sampled from older age groups in Cockburn.
Table 2The age distribution of Cockburn sample compared with the census data for Cockburn and the State
Age group / Sample / Cockburn / State0-14 / 17.3 / 23.3 / 21.4
15-24 / 15.9 / 14.2 / 14.2
25-44 / 26.4 / 32.4 / 30.0
45-64 / 25.3 / 21.4 / 23.2
65+ / 15.1 / 8.7 / 11.2
Country of Birth
Seventy one per cent of the people surveyed were Australian born, which is higher than the census estimate of 66% for Cockburn.
Marital Status
Nearly half of the people aged 16 years or older were married (46.7%), 6% were in a defacto relationship or living with partners, and just under a quarter had never been married (23.8%). Table 3 shows the proportion of adults in each category.
Table 3 Marital status of the Cockburn sample
Marital Status / Number / Per centMarried / 345 / 46.7
Living with partner/de facto / 44 / 6.0
Widowed / 89 / 12.0
Divorced / 60 / 8.1
Separated / 25 / 3.4
Never married / 176 / 23.8
Total / 739 / 100
In comparison with the Cockburn census estimate, there were less married (46.7% compared to 53.0%) and never married people (23.8% compared with 31.5%), but more widowed people (12.0% compared with 4.4%) in the sample from Cockburn.
Income and spending power
Forty three per cent of people sample had a household income below $40, 000, 39.2% between $40,000 and $80,000, and 17.7% $80,000 or more. Table 4 shows the proportion of adults in each category.
In comparison with census data, there were similar proportions of people on less than $40,000 (43% compared to 44%), more people in the median range (39% compared to 29%), and fewer people on $80,000 or more (18% compared 27%).
Table 4The annual household income of the Cockburn sample
Income range / Number / Per centLess than $20,000 / 170 / 18.8
$20,000 to $40,000 / 173 / 19.1
$40,000 to $60,000 / 170 / 18.8
$60,000 to $80,000 / 142 / 15.7
$80,000 to $100,000 / 82 / 9.1
Over $100,000 / 59 / 6.5
Refused / 108 / 11.9
Total / 904 / 100
Twelve per cent of the Cockburn sample refused to answer the income question. The refusal rate was lower in Cockburn compared with the State (11.9% versus 16%).
People were also asked about their overall spending power (Table 5).
Table 5Spending power of the Cockburn sample
Spending power / Number / Per centWe are spending more money than we get / 56 / 6.3
We have just enough money to get us through to the next pay / 212 / 23.8
There is some money left over each week but we just spend it / 70 / 7.9
We can save a bit every now and then / 423 / 47.5
We can save a lot / 129 / 14.5
Total / 890 / 100
One quarter of the people had only just enough money each week, nearly half saved a little occasionally and 14.5% could save a lot. A small group (6.3%) said that they spent more money than they got.
Employment status
Almost three quarters of people aged 16 years or older were employed (71.2%) and 2.8%
were unemployed. One quarter of the unemployed people (25.4%) were actively seeking employment. Table 6 presents the per cent of people in each category.
A higher proportion of people reported being employed (71% compared to 61%) and less people were unemployed (3% compared 5%) compared with census estimates from Cockburn.
Table 6Employment status of the Cockburn sample
Current employment Status / Number / Per centSelf-employed / 46 / 7.6
Employed for wages, / 345 / 57.3
Unemployed / 23 / 3.8
Engaged in home duties / 75 / 12.5
Retired / 40 / 6.6
Unable to work / 21 / 3.5
A student / 49 / 8.1
Other / 3 / 0.5
Total / 602 / 100
Education
Table 7 presents the level of education reported by the Cockburn sample. Just over half of adults surveyed had completed at least Year 10 or Year 12 (53%). One quarter had completed a TAFE or Trade Certificate or Diploma and 16% had university qualifications.
Table 7 Education level attained by Cockburn sample
Highest level of education attained / Number / Per centSome/Completed Primary School / 30 / 5.3
Completed Year 10 / 169 / 29.7
Completed Year 12 / 140 / 24.6
TAFE or Trade Certificate or Diploma / 153 / 26.9
Tertiary / 92 / 16.2
Other / 15 / 2.6
Total / 569 / 100
The census data indicated that there was similar proportion of people with TAFE or Trade certification or Diploma (27% compared with 25%), though more people surveyed had tertiary qualifications (16% compared with 7%).
The survey did not collect information on occupation or sector (industry) of employment, however the Cockburn census provides estimates on employment. The largest proportion of Cockburn residents were employed as intermediate clerical, sales or service workers (18.1%) and tradespersons (16%). Professionals (12.3%) and associate professionals (11.5%) were the next most common occupations, followed by labourers (10%). The Retail industry had the highest per cent of people employed (16.5%) followed by Manufacturing, (15.2%), Property and Business Services, (9.5%), Health and Community services (9.2%), Construction (8.1%) and Education (5.9%).
The Kwinana sample
Age and Sex
Kwinana has a population of 20,812 people. Table eight presents the age and sex distribution of the Kwinana sample.
Table 8Kwinana sample by age and sex
Age Group / Female / Male / Persons0 to 4 / 25 / 24 / 49
5 to 9 / 31 / 22 / 53
10 to 15 / 30 / 40 / 70
16 to 19 / 31 / 31 / 62
20 to 24 / 42 / 27 / 69
25 to 29 / 29 / 22 / 51
30 to 34 / 43 / 22 / 65
35 to 39 / 37 / 29 / 66
40 to 44 / 28 / 28 / 56
45 to 49 / 31 / 27 / 58
50 to 54 / 42 / 27 / 69
55 to 59 / 61 / 48 / 109
60 to 64 / 62 / 33 / 95
65 to 69 / 45 / 41 / 86
70 to 74 / 34 / 25 / 59
75 to 79 / 29 / 7 / 36
80 to 84 / 21 / 6 / 27
85 & over / 4 / 3 / 7
Total / 625 / 462 / 1087
Table 9 indicates that the survey sampled less people from the 15-24 year age group and more from the oldest age group compared with Kwinana and the State census estimates1,3.
Table 9The age distribution of Kwinana sample compared with the census for Kwinana and the State
Age group / Sample / Kwinana / State0-14 / 20.0 / 25.2 / 21.4
15-24 / 9.6 / 13.7 / 14.2
25-44 / 31.1 / 31.4 / 30.0
45-64 / 27.4 / 20.7 / 23.2
65+ / 11.9 / 9.0 / 11.2
Country of Birth
Sixty one per cent of Kwinana people surveyed were Australian born, which is similar to the census estimate for Kwinana (66.4%).
Marital Status
Just under half of the adults sampled were married (47.1%), 12.8% were divorced or separated people, 19.2% had never been married and 12.5% of people were widowed. Table 10 shows the proportion of adults in each category. In comparison with the census estimates, there were similar proportions of married (47.1% compared with 47.5%) and divorced or separated people (12.8% compared with 14.1%). However, there were less never married people (19.2% compared with 33.8%) and more widowed people (12.5% compared with 4%) the sample.
Table 10 Marital status of the Kwinana sample
Marital Status / Number / Per centMarried / 430 / 47.1
Living with a partner/de facto / 77 / 8.4
Widowed / 114 / 12.5
Divorced / 81 / 8.9
Separated / 36 / 3.9
Never married / 175 / 19.2
Total / 913 / 100
Income and spending power
Nearly two thirds of people surveyed from Kwinana had a income of less than $40,000 (62%), 29% earned $40,000 to $80,000 and 8.3% more than $80,000. Thirteen per cent of the Kwinana sample refused to answer the income question. The refusal rate was lower in Kwinana compared with the State (13% versus 16%).In comparison with the survey estimates there were similar proportions with an income of less than $40,000 (62% compared with 61%), more earned $40,000 to $80,000 (29% compared with 19%), and less people earning more than $80,000 (8.3% compared with 19%).Table 11 presents the annual household income for the Kwinana sample.
Table 11 Annual Income for the Kwinana sample
Income Level / Number / Per centLess than $20,000 / 277 / 25.5
$20,000 to $40,000 / 313 / 28.8
$40,000 to $60,000 / 179 / 16.5
$60,000 to $80,000 / 99 / 9.1
$80,000 to $100,000 / 47 / 4.3
Over $100,000 / 31 / 2.9
Refused / 141 / 13.0
Total / 1087 / 100
Table 12 presents the spending power of people sampled in Kwinana.
Table 12 Spending Power for the Kwinana sample
Spending Power / Number / Per centI am/we are spending more money than we get / 72 / 6.8
I/we have just enough money to get us through to the next pay / 291 / 27.6
There is some money left over each week but I/we just spend it / 89 / 8.5
I/we can save a bit every now and then / 472 / 44.8
I/we can save a lot / 129 / 12.3
Total / 1053 / 100
Nearly half of the sample were able to save a little money occasionally (45%), 27% had just enough money each week, 12% were able to save ‘a lot’ and 7% spent more money than they got
Employment status
Two thirds of the people aged 16 years and older were employed. A further 3.3% were unemployed and of these, 66.7% were currently seeking employment. Table 13 shows the proportion of people in each category. Compared with the census estimates a higher proportion of people reported being employed (54% compared with 49%) and less were unemployed (3% compared with 7%).
Table 13 The employment status of the Kwinana sample
Current employment Status / Number / Per centSelf-employed / 67 / 9.6
Employed for wages, salary or payment in kind / 309 / 44.2
Unemployed / 34 / 4.9
Engaged in home duties / 113 / 16.2
Retired / 62 / 8.9
Unable to work / 47 / 6.7
A student / 54 / 7.7
Other / 13 / 1.9
Total / 699 / 100
Educational Status
Nearly two thirds of people surveyed (61%) had completed Year 10 or Year 12. Another 30% of people had completed a TAFE or Trade certificate or Diploma and 5.6% had a tertiary qualification (Table 14).
Table 14 Education level attained by the Kwinana sample
Highest level of education attained / Number / Per centSome/Completed Primary School / 41 / 5.9
Completed Year 10 / 271 / 38.8
Completed Year 12 / 133 / 19.1
TAFE or Trade Certificate or Diploma / 178 / 25.5
Tertiary / 50 / 7.2
Other / 25 / 3.6
Total / 698 / 100
In comparison with the Kwinana census estimates, more people had completed a TAFE or Trade certificate or Diploma (census: 20.9%) and there was a higher proportion of people with tertiary qualifications (census: 3.4%).
The survey did not collect information on occupation or sector (industry) of employment, however the Kwinana census provides estimates of the distribution of types and places of employment. The Manufacturing, (19.1%), had the highest per cent of people employed followed by Retail industry (17.2%) Property and Business Services (9%), Construction (8%) Health and Community Services (8%) and Education (4.2%). Most Kwinana residents were employed as Tradespersons and Related workers (18.3%) and Intermediate Clerical or Service workers (16.6%), followed by Labourers and Related workers (13.3%), Associate professionals (9.6%) and Professionals (7.6%).
Rockingham
Age and Sex
Rockingham has a population of 70,306 people. Table 15 presents the age and sex distribution of the Rockingham sample.
Table 15 Rockingham sample by age and sex
Age Group / Female / Male / Persons0 to 4 yrs / 31 / 37 / 68
5 to 9 yrs / 37 / 41 / 78
10 to 15 yrs / 50 / 47 / 97
16 to 19 yrs / 38 / 45 / 83
20 to 24 yrs / 45 / 34 / 79
25 to 29 yrs / 26 / 23 / 49
30 to 34 yrs / 44 / 28 / 72
35 to 39 yrs / 45 / 24 / 69
40 to 44 yrs / 36 / 40 / 76
45 to 49 yrs / 43 / 32 / 75
50 to 54 yrs / 53 / 36 / 89
55 to 59 yrs / 60 / 38 / 98
60 to 64 yrs / 54 / 30 / 84
65 to 69 yrs / 43 / 33 / 76
70 to 74 yrs / 40 / 28 / 68
75 to 79 yrs / 31 / 29 / 60
80 to 84 yrs / 13 / 5 / 18
85 & ove9r yrs / 5 / 1 / 6
Total / 694 / 551 / 1245
Table 16 indicates that the survey sampled less people from youngest and more older people compared with Rockingham and State census estimates 1,4.
Table 16 The age distribution of the Rockingham sample compared with the census for Rockingham and the State
Age group / Sample / Rockingham / State0-14 / 17.8 / 25.1 / 21.4
15-24 / 14.3 / 13 / 14.2
25-44 / 21.5 / 29.4 / 30
45-64 / 28.0 / 20.9 / 23.2
65+ / 18.4 / 11.6 / 11.2
Total / 100 / 100 / 100
Country of Birth
Seventy per cent of the Rockingham were Australian born, which is the same as the Rockingham census estimate.
Marital status
Just over half of the adults surveyed were married (53%) and 9.6% were divorced or separated. Only 19% had never been married and 12.4% were widowed. In comparison with the Rockingham census estimates, there was a similar proportion of married people (53% compared with 54.7%), and divorced or separated people (9.6% compared with 10.6%). However, there were less never married (census: 27.4%) and more widowed people in the sample (12.4% compared with 5.4%).
Table 17 Marital status of the Rockingham sample
Marital Status / Number / Per centMarried / 531 / 53.0
Living with a partner/de facto / 61 / 6.1
Widowed / 124 / 12.4
Divorced / 61 / 6.1
Separated / 35 / 3.5
Never married / 190 / 19.0
Total / 1002 / 100
Income and spending power
Table 18 presents the annual household income for the Rockingham sample.
Table 18 The annual income of the Rockingham sample
Annual Income / Number / Per centless than $20,000 / 240 / 19.4
$20,000 to $40,000 / 268 / 21.7
$40,000 to $60,000 / 255 / 20.6
$60,000 to $80,000 / 177 / 14.4
$80,000 to $100,000 / 89 / 7.2
over $100,000 / 64 / 5.2
Refused / 142 / 11.5
Total / 1236 / 100
Just under half of people surveyed had an income of less than $40,000 (46.5%), 39.5% earned $40,000 to $80,000 and 14% more than $80,000. Twelve per cent of the Rockingham sample refused to answer the income question. The refusal rate was lower in Rockingham compared with the State (11.5% versus 16%).
In comparison with census estimates, there were less people with an income of less than $40,000 (47% compared with 55%), more people with mid-range incomes (40% compared with 21%) and less with incomes over $80,000 per annum (14% compared with 24%).
People from Rockingham were also asked about there overall spending power (Table 19).
Table 19 Spending power of the Rockingham sample
Spending Power / Number / Per centI am/we are spending more money than we get / 64 / 5.3
I/we have just enough money to get us through to the next pay / 240 / 19.9
There is some money left over each week but I/we just spend it / 106 / 8.8
I/we can save a bit every now and then / 617 / 51.1
I/we can save a lot / 180 / 14.9
Total / 1207 / 100
The largest proportion of people were able to save a little money occasionally (51.1%); 20% had only just enough money each week, 15% could save ‘a lot’ and 5% spent more money than they got each week.
Employment Status
Seventy per cent of people were employed and only 3.2% unemployed. Most unemployed people (90%) said that they were currently looking for work. Census data indicated that a higher proportion of the sample was employed (70% compared with 49%) and less were unemployed (3% versus 7%) compared with the census estimates for Kwinana.
Table 20 Employment status of the Rockingham sample
Current employment Status / Number / Per centSelf-employed / 72 / 9.3
Employed for wages / 422 / 54.6
Unemployed / 25 / 3.2
Engaged in home duties / 105 / 13.6
Retired / 72 / 9.3
Unable to work / 30 / 3.9
A student / 44 / 5.7
Other / 3 / 0.4
Total / 773 / 100
Education
Fifty six per cent of adults sampled had completed at least Year 10 or Year 12, 26% had completed a TAFE or Trade Certificate or Diploma and 12% had a Tertiary qualification (Table 21).
Table 21 Education level attained by the Rockingham sample
Highest level of education attained / Number / Per centSome/Completed Primary School / 29 / 3.8
Completed Year 10 / 235 / 30.6
Completed Year 12 / 185 / 24.1
TAFE or Trade Certificate or Diploma / 203 / 26.4
Tertiary / 89 / 11.6
Other / 27 / 3.5
Total / 768 / 100
The Rockingham census estimates indicated there were a similar proportions with a TAFE or Trade Certificate or Diploma (26% compared with 25.9%), but more people sampled had Tertiary qualifications (11.6% compared with 5.1%).
The survey did not collect information on occupation or industry of employment, however the Rockingham census provides estimates on employment. Most Rockingham residents work as Tradespersons (18.6%) and Intermediate Clerical, Sales or Service workers (16.8%) followed by Associate professionals (12.3%), professionals (10.7%) and labourers (9.6%). The Retail industry (17%) and Manufacturing (17%), had the highest proportions of people employed followed by Health and Community Services (9%), Construction (8%), Property and Business Services (8%), and Education (6%).
Conclusion
The comparisons of the areas under study with the census data illustrates that the samples selected were reasonably representative of the areas in all these main socio demographics. The data will be adjusted to the age and sex distribution of the WA ERP for 2003 and weighted for oversampling which will correct for the main contributors to ill health.
The samples can be validly used in a study comparing health status within the areas to the State.