Query to Check Oracle Database Growth

This Query Calculate the Datafile Growth on a Yearly Basis

SELECT To_char(creation_time, ‘RRRR’)         year,
To_char(creation_time, ‘MM’)           month,
Round(SUM(bytes) / 1024 / 1024 / 1024) gb 
FROM   v$datafile
GROUP  BY To_char(creation_time, ‘RRRR’),
To_char(creation_time, ‘MM’)
ORDER  BY 1,
2;