If you are required by your employer to perform your work wholly outside New York, your income is not taxable by New York. See page 7 of this web reference:
https://www.hodgsonruss.com/media/publication/915_Nonresident%20Allocation%20Guidelines%202013.pdf
This is known as the "convenience of the employer" doctrine.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
