Template:Get Years String
From Broadcast for Schools.co.uk.co.uk
{{ Get Years String | calcfirstrunfrom= | calcenddate= }}
Creates a string of a programme's run dates expressed in years, to populate Property:Broadcast years string (Template:Get Dates String handles the precise run dates for Property:Broadcast dates string. End date is recalculated so that instead of the current date & time, programmes without an end date say "present". If there is no Property:First run from then it returns null.