This is a decrease from 5.9 weeks in April 2021, a decrease from 11.5 weeks in May 2020 but an increase from 2.7 weeks in May 2019.
Mae hyn i lawr o 5.9 wythnos ym mis Ebrill 2021, i lawr o 11.5 wythnos ym mis Mai 2020 ond i fyny o 2.7 wythnos ym mis Mai 2019.