This did exactly the job required and has tidied up the index perfectly - I'm extremely grateful, gjh. I didn't do the first bit of your reply though, because I'm afraid I didn't understand what you were saying! As long as I haven't introduced a problem elsewhere that I've not found yet, I'm happy with that, but if I did need to do both parts, I'll have to come back and have another go at following what you were getting at in part A!
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