Good to hear that it's working for you.

I kept the 1st post there because it is sometimes useful to have a running count by group.

It sounds like you've got SQL Server 2008 if you've got a Date type available to you. I hate how + means concatenate and add depending on context. To get it to work in your original setup you'd need to have an inner Covert to Varchar on your [Date] column. In your case it's much better to have a DateTime column to begin with.