19 per cent of practices were closed for half a day on one or more days a week in 2011 – six percentage points lower than the previous year.
Roedd cyfartaledd o 6.1% o sesiynau hanner diwrnod wedi’u cofnodi fel absenoldeb awdurdodedig ar gyfer disgyblion 5 i 15 oed yn ystod yr wythnos ddiweddaraf, i lawr o 7.0% yr wythnos cynt.