Gross earnings per head: by place of residence from the Annual Survey of Hours and Earnings (ASHE), ONS. This data set provides information about earnings of employees who are living in an area, who are on adult rates and whose pay for the survey pay-period was not affected by absence. ASHE is based on a sample of employee jobs taken from HM Revenue & Customs PAYE records (177,000 returns in 2009). Information on earnings and hours is obtained in confidence from employers. ASHE does not cover the self-employed nor does it cover employees not paid during the reference period. The earnings information presented relates to gross pay before tax, National Insurance or other deductions, and excludes payments in kind. The confidence figure is the coefficient of variation (CV) of that estimate. The CV is the ratio of the standard error of an estimate to the estimate itself and is expressed as a percentage. The smaller the coefficient of variation the greater the accuracy of the estimate. The true value is likely to lie within +/- twice the CV. Results for 2003 and earlier exclude supplementary surveys. In 2006 there were a number of methodological changes made. The headline statistics for ASHE are based on the median rather than the mean. The median is the value below which 50 per cent of employees fall. It is ONS's preferred measure of average earnings as it is less affected by a relatively small number of very high earners and the skewed distribution of earnings. It therefore gives a better indication of typical pay than the mean. The best figure to use for comparing earnings for men and women, is the hourly earnings excluding overtime. Including overtime can distort the picture as men work relatively more overtime than women. Survey data from a sample frame, use caution if using for performance measurement and trend analysis '#' These figures are suppressed as statistically unreliable. ! Estimate and confidence interval not available since the group sample size is zero or disclosive (0-2). Visit ONS website