You are reading a single comment by @Chalfie and its replies.
Click here to read the full conversation.
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Chalfie
It sounds like less of an Excel problem (I think that part is easily solved using if statements and lookups or similar) and more an issue with clearly defining what you actually want to do in terms of replacement data.
You basically need to come up with a set of rules in terms of what you want to replace the ignored data with, e.g first option is to use current data, second option is one year before, third is ...
Once you've done that then you can do the Excel work which probably won't be too tricky. Admittedly, I'd be tempted to consider how useful the whole thing is (probably not what you want to hear), once you get to the stage of manually excluding and replacing your data because it doesn't fit the pattern then you've almost decided what you expect the output to be.