Due to the nature of the scheme, returns for the latest financial year reported (2017-18) can still be submitted past the cut-off date for the publication of these figures. As a result data for 2017-18 is not yet complete. To avoid misleading comparisons between years HMRC have compared the years 2016-17 to 2015-16 in their publication when discussing change between years, and 2017-18 when discussing in-year characteristics.