Pay statistics: the terms on this site
These are the words that come up again and again on our salary pages, defined once here so every page can link to a single, longer explanation instead of repeating it.
- Median vs. mean
The median is the middle value when every salary is lined up from lowest to highest: half earn less, half earn more. The mean is the simple average. A handful of very high salaries pulls the mean up without moving the median, so the median is usually the better guide to what a typical person earns.
- Percentile
A percentile splits the distribution into 100 equal parts. The 10th percentile is the value only a tenth of people earn below; the 90th percentile is what only a tenth earn above. Looking at several percentiles shows the full spread, not just one average.
Fonte: Annual Survey of Hours and Earnings (ASHE) — Office for National Statistics.
- Gross vs. net pay
Gross pay is what an employer pays before tax, social security and other deductions. Net pay, or take-home pay, is what actually reaches the bank account afterwards. A figure that does not say which one it is should be treated as gross, since that is what most official pay surveys publish.
- Full-time equivalent
A way of converting part-time hours into the pay a full-time version of the same job would earn, so that a two-day-a-week role can be compared fairly with a five-day one. Figures that mix full-time and part-time workers without adjusting for this tend to understate typical full-time pay.
- Coefficient of variation
A measure of how much an estimate could be off, expressed as a percentage of the estimate itself. Statistical agencies use it to flag figures based on too small a sample: a high coefficient of variation means the number should be read as a rough order of magnitude, not an exact figure.
Fonte: Annual Survey of Hours and Earnings (ASHE) — Office for National Statistics.
- Pay scale
A published table of fixed pay points or bands that an employer, usually in the public sector, must follow for a given role — for example an NHS band or a police rank. Pay within the scale usually rises with time served rather than being negotiated case by case.
- Collective agreement
A pay and conditions deal negotiated between an employer or employer group and a trade union, binding on everyone it covers. Public-sector pay scales are usually set this way, which is why they change on a fixed schedule rather than whenever an individual employer chooses.
- Minimum wage
The lowest hourly or monthly pay an employer is legally allowed to offer. It is a floor, not a typical salary, and it says little on its own about what a specific occupation actually pays — some countries set it by law, others leave wage floors to sector agreements instead.
- Reference period
The point in time, or the stretch of time, that a published figure actually describes. Pay surveys take months to collect and process, so the reference period is usually well before the date the figures are released, and always before the date you are reading them.
- Occupational classification
A standard code that groups similar jobs so that pay statistics can be compared across employers and over time — the UK uses SOC, Canada uses NOC, the United States uses SOC as well, and the European Union uses ISCO. The same job title can sit in different codes depending on the classification used.
Fonte: Occupational Employment and Wage Statistics (OEWS) — U.S. Bureau of Labor Statistics.