SQL Server : round and add percent sign

select 
    --Cast(Round(count(*) * 100.0 / sum(count(*)), 0) as nvarchar(5) + '%' 
      CAST(Round(count(*) * 100.0 / sum(count(*)), 0) as nvarchar(5)) + '%'
from 
    db_table_MetaData

This should do the trick.

In essence you take the 08/15 ROUND() function to get your numeric value. After this you cast it into a nvarchar(x) and add a string to your string. However I have no method of checking my syntax right now.