I determine UK income inequality levels and trends by combining inequality estimates from tax return data (for the "rich") and household survey data (for the "non-rich"), taking advantage of the better coverage of top incomes in tax return data (which I demonstrate) and creating income variables...

Survey under-coverage of top incomes leads to bias in survey-based estimates of overall income inequality. Using income tax record data in combination with survey data is a potential approach to address the problem; we consider here the UK's pioneering "SPI adjustment" method that implements...