2023 - Seeds and Stuff I've bought/acquired

Do I see next year’s challenge coming on ?   

That's exactly what I was thinking, but am I brave enough?

How about checking in each month with the amount you've spent on your garden? Maybe adding a value for whatever you've grown as well so that, at year end, you'd have an idea whether your garden pays for itself financially.
I'm not very good at keeping records that involve weighing stuff so perhaps we can come up with a nominal amount for each portion of food that's eaten or frozen. For example - a courgette, serving of beans, bowl of raspberries, mixed leaf salad would all be "worth" the same - perhaps 50p if you estimate how much they would cost to buy. 
Using my figures this year of spending £1 a day, if I ate 2 portions of homegrown something a day it would balance out. In winter, there'd be very little produce compared to summer so I'd be relying on summer crops to make up for winter. 
Does any of this make sense?

Sounds like a plan.  I wasn’t sure how to work out the value of what I harvest. I was going to roughly compare to Tesco prices. I like your way better.