I assume your X axis is already a date? Otherwise how can management expect you to add a date.
YOu can change x axis to use a formula
@Year/Mth
totext(year(yourdatefield),0,"")&"/"&totext(month(yourdatefield),"00",0,"")
This will group all your dates as
YYYY/MM
You need to do it this way so that months will follow year/ month chronological order.
Ian