What's the most efficient way of operating with fields in MySQL?

I have the following query: SELECT DATE(utimestamp) as utimestamp, name, data*2000000 from tData where utimestamp BETWEEN '2016-01-01 00:00:00' AND '2016-04-16 00:00:00' AND name = 'Valor2' and data>20 group by YEAR(utimestamp), MONTH(utimestamp), name union SELECT DATE(utimestamp) as utimestamp, name, data*0.1 from tData where utimestamp BETWEEN '2016-01-01 00:00:00' AND '2016-04-16 00:00:00' AND name = 'Valor1' and data>20 group by YEAR(utimestamp), MONTH(utimestamp), name order by utimestamp asc Is there a more efficient way of operating with 'data'? Is there a way of doing this without using UNION?