People ask me how long it takes me to do a painting. I know what they mean, but to that question there is no timely answer. The question does not relate to art. Maybe making a ceramic bowl or quilt, or something in the craft arena it would, but in the arts, as with dance, music, theater, painting, etc. it has no relevancy. Time has no meaning in the creation of art. Art exists, when it is done.
I personally respond to that question, with, "My art takes as long to make as it does to say what I need to say, and not even I know the answer to that" ~ russ potak