Data on Mandatory Reconsiderations (MR) and appeals for initial decisions following a PIP assessment can be found in Table 5A of the “Data tables: PIP award rates, clearance/outstanding times and tracking of initial decisions following a PIP assessment through to mandatory reconsiderations or appeals, to October 2019” available here: https://www.gov.uk/government/statistics/personal-independence-payment-april-2013-to-october-2019