Ok cool, thank you for this! I’m certain that this is some truly spectacular advice you have give here. But I'm two pints into my Friday evening so I'm afraid all I can give in reply at the moment is my gratitude. This looks like some good options for to look into on Monday. I've not yet ventured into R much yet but I it's probably best to learn how to do this properly now while I have the time. Thanks again, i really appreciate your input.