Fifty cities provided information on vacancy rates (in percent) in local apartments in the following frequency distribution. The sample mean and the sample standard deviation are 9% and 3.6%, respectively.

Vacancy Rate (in percent) .................. Frequency

Less than 6 ........................................ 10

6 up to 9 ............................................ 10

9 up to 12 .......................................... 20

12 or more ......................................... 10

Apply the goodness-of-fit test for normality at the 5% significance level. Do the sample data suggest that vacancy rates do not follow the normal distribution?