That is a nice little query. Here's my quick re-write to show all databases and track percent growth since the first backup on record.

SELECT

'database_name' = mdbus.database_name

,'backup_start' = mdbus.backup_start_date

,'duration' = CASE

WHEN (datediff([second], mdbus.backup_start_date, mdbus.backup_finish_date) / 60 / 60) >= 100 THEN '100+ hours'

ELSE isnull(

right('0' + cast( (datediff([millisecond], mdbus.backup_start_date, mdbus.backup_finish_date) / 1000 / 60 / 60) AS varchar(10)), 2)

+ ':' + right('0' + cast(((datediff([millisecond], mdbus.backup_start_date, mdbus.backup_finish_date) / 1000 / 60) % 60) AS varchar(10)), 2)

+ ':' + right('0' + cast(((datediff([millisecond], mdbus.backup_start_date, mdbus.backup_finish_date) / 1000) % 60) AS varchar(10)), 2)

+ '.' + right('00' + cast( (datediff([millisecond], mdbus.backup_start_date, mdbus.backup_finish_date) % 1000) AS varchar(10)), 3)

, '')

END

,'size_gb' = convert(decimal(10,2), (convert(float, mdbus.backup_size) / 1024 / 1024 / 1024))

,'percent_growth' = convert(decimal(10,2), (((convert(float, mdbus.backup_size) - mdbus_first.backup_size) / mdbus_first.backup_size) * 100))

FROM

msdb.dbo.backupset mdbus

INNER JOIN

(

SELECT

database_name

,'backup_set_id' = min(backup_set_id)

FROM

msdb.dbo.backupset

GROUP BY

database_name

) mdbus_first_rec ON (mdbus.database_name = mdbus_first_rec.database_name)

INNER JOIN

(

SELECT

database_name

,backup_set_id

,backup_start_date

,backup_size

FROM

msdb.dbo.backupset

) mdbus_first ON (mdbus.database_name = mdbus_first.database_name AND mdbus_first_rec.backup_set_id = mdbus_first.backup_set_id)

WHERE

mdbus.[type] = 'd'

ORDER BY

mdbus.database_name

,mdbus.backup_start_date DESC