Changing Order of Calendars on Imac?

Does anyone know how to change the orders of calendars in ical? I am trying to move the top calendar down so that I can delete it. I can move the ones below around but not the top calendar which cannot be deleted unless it is moved down. I tried changing the order in icloud but it didn't change them on my mac. Pls advise if you know how to do this. Thanks.