In December, the proportion of all calls that were immediately life-threatening was 14.3%, up from 13.8% in November, and the second highest on record.
Ym mis Rhagfyr, roedd cyfran yr holl alwadau lle’r oedd bywyd yn y fantol yn 14.3%, i fyny o 13.8% ym mis Tachwedd, a’r ail ffigur uchaf ar gofnod.