Just because your survey score has gone down, or up, doesn't mean that there has actually been a change in the overall business NPS®. It might just be a fluke of the sample you have collected.
Using advanced statistics, this tool will confirm if the change is real:
To use just enter the number of Promoters, Neutrals, Detractors in your survey.
Please note that the Net Promoter Comparison Tester is provided on an as is basis and Genroe accept no liability for its use in any way whatsoever.