Your question is Testing an NPS Decline. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You are reviewing a monthly customer survey for a product surface. The latest NPS is lower than last month, and you need to judge whether the drop is likely real or just sampling noise.
How would you determine whether a decline in NPS is statistically meaningful?