Shapiro-Wilk
Statistic df Sig.
January .915 33 .013
February .872 33 .001
March .888 33 .003
April .877 33 .001
May .963 33 .312
June .869 33 .001
July .891 33 .003
August .862 33 .001
September .859 33 .001
October .962 33 .286
November .979 33 .757
December .963 33 .311
Table 1: Tests of Normality