Obviously if your members are entering the data themselves there will need to be a degree of honesty from them.
One way would be to have a forum for the year and each member created their own topic where after each event they would enter their mileage, and then at the end of the year you would go through and add them all up.
Another option could be to have one topic where each member would have a reply which they could edit with their milrage.
There is nothing within phpBB that would automatically calculate the annual total - for that you would need an extension.
Remember: You only know what you know and - you don't know what you don't know!
My CDB Contributions | How to install an extension
I will not be accepting translations for any of my extensions in Github - please post any translations in the appropriate topic.
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