X-axis in bar graph

[Mark4]

Can anyone tell me why the negative months aren't ascending?

=Replace(Class([Req Projected Need Lead Time Days]/30, 3), '<= x <','-')

[sunny_talwar]

May be use a dual function here

=Dual(
Replace(Class([Req Projected Need Lead Time Days]/30, 3), '<= x <','-'),
Class([Req Projected Need Lead Time Days]/30, 3) 
)