Script to estimate the Size of log backups

We have an environment where we constantly need to estimate the size of log backups(.Trn file size). I use this script to achieve it.  

create table #dbcclogspace([Database Name] nvarchar(200),[Log Size (MB)] float,[Log Space Used (%)] float,[Status] int)
     insert into #dbcclogspace([Database Name],[Log Size (MB)],[Log Space Used (%)],[Status])
      exec('DBCC sqlperf(logspace)')
     select [Database Name],([Log Space Used (%)]*[Log Size (MB)])/100 as [LogBackupSize in MB],(([Log Space Used (%)]*[Log Size (MB)])/100)/1024 as [LogBackupSize in GB] from #dbcclogspace
     drop table #dbcclogspace