Yesterday, I added up my income numbers for 2015. I made slightly more gross income this past year than I made the year before. Since my expenses were a tad less in 2015 than in 2014, my net income for this past year was also more than my net for 2014. 79.4% of that 2015 income came from my stores, whereas only 72% of my 2014 income came from my stores. Although I cut back on the amount of work I did for publications, I still saw an increase. That tells me I am justified in continuing to concentrate on work for my stores and doing work for publications only on occasion. I'm still willing to do work for publications on assignment/commission, but I doubt I'll be doing much work to send out as unsolicited submissions. It just doesn't seem worth it anymore.
Of course, since I'm still nowhere near making a living off of my art, it's all relative. However, it's always nice to see an increase from one year to the next. And, yes, my income gets reported to the IRS, and I do pay self-employment tax on that income.