Show oldest to newest of a date range field I am trying to figure a way to show the oldest to the newest of a date range field that is attached to a taxonomy. 

For example: Tax1 (1900-1920), Tax2 (1913-1950), Tax3 (1970-1980)

So how shall I printed like this: (1900-1980)?
1) Split your taxonomy values by (-).

2) Store all the values into an array.

3) Find minimum &amp; maximum value from that array.

Ex:


  $date = array(1900, 1920, 1913, 1950, 1970, 1980);
  
  $result = min($date) . ' - ' . max($date);