Calendars should not be longer than 10 years. If you really need such long periods you need to split them up.
Ní cheadaítear d' fhéilire a bheith níos faide ná deich mbliana. Má tá a leithéid d' fhéilire de dhíth ort i ndáiríre, caithfidh tú iad a roinnt.