Targets are good, but this strikes me as a somewhat artificial target. As if the width was everything, the quality less important.
When I was doing this as my day job, and only source of income, I always set a thousand-words-a-day target. I didn't always meet it. I felt then, and I still feel, it's the effort which the target encourages which is valuable rather than the word-count at the end of the day.
Still, different things work for different people. If you find this helpful, good luck with it.
