labels on x axis from vba is acting weird
 

I have some vba that I use to generate charts.
Here is the first few lines:
Application.ScreenUpdating = False
Sheets("Data (altered)").Select
Range("r8:r12,t8:v12").Select
'Range("t8").Activate
Charts.Add
ActiveChart.ChartType = xlColumnClustered
ActiveChart.SetSourceData Source:=Sheets("data
(altered)").Range("r8:r12,t8:v12"), _
PlotBy:=xlColumns

The problem is that the value of t8 is supposed to be a label along the
x axis. However, the label appears as a concatenation of t8 and t9,
where as the other labels, u8 and v8 works fine.

Why would this happen?

TIA