The following table provides the definitions for each measure in the tables included in this release and also those available from the Statistics NZ website. Other necessary definitions are:
- The calendar year is divided into four quarters of three months and referred to as quarter one through to four. The latest quarter is the ‘reference quarter’.
- The ‘reference date’ is the 15th of the middle month of the reference quarter.
- ‘Full quarter jobs' are jobs which exist continuously over the reference quarter.
- All earnings measures represent quarterly earnings.
- All earning measures are inclusive of tax.
- All earnings measures include payments reported as lump sums to the Inland Revenue.
|Total filled jobs
||The number of jobs on the 15th of the middle month of the reference quarter.
||An indicator of economic activity.|
||The number of new employees who have joined employers since the previous reference date.
||What industries or regions are gaining or losing the most workers?|
What industries or regions are gaining or losing older or younger workers. Are there differences by sex?
||The number of employees who have left employers since the previous reference date.
|Worker turnover rate
||The ratio of the average of the total accessions and separations to the average of the total jobs in the reference quarter (t) and the previous quarter (t-1), as represented in the formula:
(Accessions + Separations)/2
(Jobst + Jobst-1)/2
|A measure of workforce stability, the turnover rate reflects the movement of workers into and out of jobs.|
What types of workers (age, sex) have higher or lower turnover rates?
||The number of jobs created, since the previous reference date, when businesses expand or start up.
For example, a business employing 100 workers with 10 accessions and 5 separations has job creation of 5.
|What industries, sector or regions are creating or destroying jobs?|
||The number of jobs lost, since the previous reference date, when businesses contract or shut down.
For example, a business employing 100 workers with 5 accessions and 15 separations has job destruction of 10.
|To what extent do job creation or destruction rates vary by firm size or other firm characteristics?|
||Mean or median earnings of all full quarter jobs.
||What industries or regions have the highest or lowest mean or median earnings?|
|Mean earnings for continuing jobs
||Mean or median earnings for jobs which were full quarter in the reference and previous quarters.
||How do earnings for new employees compare with those for existing employees?|
What are the earnings outcomes for these different groups?
|Median earnings for continuing jobs|
|Mean earnings for
|Mean or median earnings for jobs which were full quarter in the reference quarter and began sometime in the previous quarter, but were not present in the previous four quarters.|
|Median earnings for new hires|
|Mean earnings ratio
||The ratio of the mean or median earnings for new hires to the mean or median earnings for continuing jobs.|
|Median earnings ratio|
||The sum of all earnings paid in the reference quarter, including employees with invalid IRD identifiers and individuals under 15 years of age.
||An indicator of economic activity.|
Accessions, separations and worker turnover rate
The worker turnover rate is calculated using the counts of accessions and separations, which are defined using the reference date concept. Other workers may join and leave during the reference quarter but not be present at either reference date. These workers are not included in the counts of accessions or separations and are therefore excluded from the worker turnover rate.
The worker turnover rate is calculated at the geographic unit level, not the enterprise level. This means that employees who transfer between geographic units within an enterprise will be counted as accessions and separations.
Net job change
The difference between the counts of job creation and job destruction (job flows) is equal to the total change in jobs at the aggregate level, the net job change. Job flows reveal the amount of job turnover at the business level underlying the net job change. Similarly, the difference between the counts of accessions and separations (worker flows) is also equal to the net job change. Worker flows reveal the turnover of individual employees underlying the net job change.
These relationships do not necessarily hold for sub-national breakdowns. Businesses and individuals may change characteristics such as industry or age group over time. This causes a change in the total jobs for that characteristic but does not affect the job or worker flows.
Further explanation of the measures
Count statistics are taken on the 15th day of the middle month of the quarter – the ‘reference date’ – whereas earnings statistics are based on the ‘full quarter’ concept. The following figure is provided for further explanation of the measures and these characteristics. In the first part of the figure the reference quarter is shown by the shaded area. The timing of several distinct jobs is represented by the black bars. The second part of the figure shows which measures these jobs are included in.
Note: it is assumed in this figure that jobs 1 and 2 were not present in the previous four quarters.
Patterns in the data
The counts of job creation and destruction, and worker accessions and separations, show an obvious seasonal pattern. This pattern is largely caused by the annual update of employee counts on the BF, resulting in larger counts of destruction and creation in one quarter than in the other three.
This seasonal pattern changes from the March 2003 quarter. This change is caused by the implementation of a programme to improve the BF maintenance practices and a consequent change in LEED methodology. Methods are being investigated to minimise the changes caused by administrative updating processes.
Frequency of outputs
LEED job measures are generated as a quarterly series, although tax data is received monthly. This is done to reduce volatility caused by the variable number of pays per month and to ensure comparability with other statistics.
Timing of the measures
LEED measures are produced as counts of jobs at a point-in-time, or means and medians of earnings for jobs existing for a full quarter.
Counts of jobs or workers are taken on the 15th of the middle month of the quarter.
Measures relating to means and median earnings are produced using the full-quarter concept. A disadvantage of the point-in-time approach is that the earnings for a job relate to the entire month regardless of the actual days worked. Therefore mean or median earning statistics per job, produced under this concept, would include people who worked one day (or even one hour) in the month, with people who worked all month. The use of the full-quarter concept corrects for this.
The total earnings measure uses neither the point-in-time or full-quarter concept and is instead a simple sum of all earnings paid out at any time in the reference quarter.
Timeframe for production
The timeliness of LEED is dependent on a number of factors:
- Employers take time to complete their EMS schedules and supply them to Inland Revenue.
- Inland Revenue requires time for processing and supply to Statistics NZ.
- Statistics NZ requires further time for receipt, data transformation and the production of output data.
- The derivation of full-quarter outputs requires data for an additional quarter after the reference quarter.
In addition, late returns and updates are received in LEED well after the end of the reference period. These can distort the measures produced, particularly the estimates of change.
The effect of these late returns on the measures was investigated during the development of the dataset. It was found that the measures trended towards their true values over time. The majority of late returns are received by 18 months after the reference quarter and further updates have little impact on the measures. The manner in which the measures approach this 18-month point is similar to that represented in the graph below.
The LEED data will be developed to include measures on self-employed workers. These will be included in annual releases relating to individual workers with measures such as length of job tenure, spells of employment and number of jobs held.
Further measures may be provided in future quarterly releases in response to user interest.
Some of the outputs produced in this release may be revised with the development of future measures or as a result of enhancements to existing methods.