Nice! I keep track of my commute times (sometimes, strava or endomondo or something automatic would be easier); my commute is a little under 6mi, my first entry was 10.59mph.

Last Friday was my first commute for time after a couple months of taking it easy from a back issue; crushed my previous personal best by 2.5min!

There will be ups and downs, but if you track regularly and work at it, you will enjoy a downward trend!