you said: "You have historical data,"
I only had enough sales data for a week or two.
now I have a better idea of what is going on. I estimate 1 good photo can be worth from $5 to a max of $20 annually.
I said that three days ago. But even with the three weeks you said you'd been on there, you still had historical data. Not enough to give you any kind of accurate forecast, but it's going to be a lot more accurate than people who don't have the data, and are just guessing what you might make over the period of a year.
So, based on your figures, you could make anything up to $600k a year. Sounds pretty good. Although, you'll only find out what a 'good' photo is if and when it starts selling... better to use an average across all images.