Review on SPC for Excel by Tony Francis

I like that it's easy to use, has many features (such as calculating historical averages) which are not available in most spreadsheets out there today! The interface could be more intuitive - sometimes you need help figuring things such an how much space should go where when creating graphs or tables etc., but these issues can easily been solved with some training from support staff at Microsoft itself if they're willing/able too provide this service free-of charge!! Very good product overall though; very powerful tool indeed once used properly by someone who knows what he / she needs vs wants versus doesn't know about yet.

It helps me calculate cost per unit sold over time periods along side sales figures so i'm able tot make informed decisions regarding future production plans without having access ot actual data sheets myself via excel spreadsheet format only. !