I am keeping a Nature "Springwatch" calendar using a standard Excel spreadsheet. I have a list of the indicator species in column A.
There are then two columns for each year. As I note something e.g. 'First plum blossom', I then enter the date in the first column for that year. The Cell format is Category = Date; Type = *14/03/2001 Locale = English (UK). Excel version is 2007
What I am trying to do in the second column for each year is to show the number of days variance, as either a +/- over this year, from last year. So if the date was 10 days earlier than last year, it would be '-10', if it was 10 days later, it would be '+10'.
So far, I am unable to find a way to achive this.
Thanks for reading.