Derived income variables

Income from a variety of sources is measured through a number of questions, some of which are used to also create derived variables (these are discussed on the Derived variables page).

Top-coding of income variables

Because extremely high incomes are rare, releasing this information can increase the risk of disclosure. Therefore to ensure that people with a very high income are not identifiable in any way, reported income beyond a certain amount is top-coded to a maximum annual value of £180,000. Some income variables can be reported on rates other than an annual basis. In these cases, values are top-coded to an equivalent amount for the relevant period (for example, £15,000 for a monthly reported value being equivalent to £180,000 per year). The variables affected by this top-coding and the maximum annual values are reported in the table below.

Top-coded variables and maximum value

Variable	Description	Top-coded value
w_fiyrdia	Amount received in interest/dividends	180,000
w_fiyrdic_dv	Income from savings and investments (annual)	180,000
w_j2pay	Gross earnings from seconds jobs last month	15,000
w_paygu_dv	Usual gross pay per month: current job	15,000
w_paynu_dv	Usual net pay per month: current job	15,000
w_payu_dv	Usual pay per month	15,000
w_payu	Usual pay	180,000
w_payg_dv	Gross pay per month in current job: last payment	15,000
w_payn_dv	Net pay per month in current job: last payment	15,000
w_jsprf	Self-employed: net profit in last yearly account	180,000
w_jspayu	Average income from job/business	15,000
w_seearngrs_dv	Self-employment earnings – gross	15,000
w_fimnlabgrs_dv	Total monthly labour income – gross	15,000
w_fimngrs_dv	Total personal income – gross	15,000
w_paygl	Gross pay at last payment	180,000
w_paynl	Net pay at last payment	180,000