The difference between Year 2 and 4 learners’ attainment, as shown by the dark blue arrow, converts to 24 months (as the Year 4 learners have been in school 24 months longer than the Year 2s).
Mae’r gwahaniaeth hwn hyd yn oed yn fwy amlwg ar gyfer pobl ifanc 19 i 24 oed o gymharu â phobl ifanc 16 i 18 oed.