I don't think the Reports page on the Smart Things app is functional. Every time I check it, it says that the highest consumption is between 20:00 and 21:00, which is nonsense. It also says that I used an above-average amount on a random day of the week, which I would expect to be a day on which I used my washing machine and tumble dryer, but it never is!
That seems odd, @Ray42. It may be best to drop our SmartThings specialists an email regarding this. The email address to contact is support@smartthings.co.uk.