I added up my expenses: about $120/year for soil, $75/year for nutrients, $150/year for bulbs, and around $360/year for electricity, so a total of $705/year, which is $58.75/month. In the average month, I get around 4 ounces, so about $15/ounce, and an ounce lasts us a month, so about fifty cents a day to keep us supplied with kickass pot. (When I have too much, I just stop growing.) My monthly satellite bill is about six times my monthly pot bill, now that I look at the math. Outrageous!