In a benchmark study the performance of a functional is determined by the deviations from the reference values, calculated as RE/BH DF A -RE/BH ref. , so we can test the applicability of the CPS extrapolation approach for calculating benchmarks through the observed changes in MADs of a selected set of DFAs when each level of theory is used as the reference method. For the DFAs listed in table 1 we calculate three sets of MADs using our reference levels of theory of interest: DLPNO-CCSD(T)/CBS (3,4) with either CPS (5,6), standard TightPNO or CPS(6,7) (in order of increasing accuracy). Our main analysis herein focuses on the results for the DFAs in their DFT-D3-corrected (or VV10-corrected, where applicable) forms, while results of the functionals plain and with DFT-D4 are given in the Supporting Information.