The answer changes throughout the year! Arizona (except the Navajo Nation) does not observe daylight saving time, but New York does. This creates varying time differences:
During US daylight saving time (March to November): Phoenix is 3 hours behind New York.
During US standard time (November to March): Phoenix is 2 hours behind New York.
Any business hours work well! 9:00 AM - 5:00 PM New York corresponds to 6:00 AM - 2:00 PM Phoenix (during DST) or 7:00 AM - 3:00 PM Phoenix (during standard time).
Phoenix is one of America's fastest-growing metros, attracting many transplants from the Northeast. Arizona's decision not to observe DST was made in 1968 due to the extreme summer heat - adding an extra hour of sunlight wasn't desirable!