| I rarely need to change mine more than 1 or two units. I've just had an unusual need to lower 3-4 units (from 24-25 units down to 21)...which has been the biggest reduction for me in a while.
Several reasons that I can imagine...
1) I've lost a few pounds...not much...but I'm only 5'2" and a pound or two makes a big difference in how I "feel".
2) Summer temps...although I'm no longer in an extreme cold winter area...the last few weeks have been warmer than the mild winter.
3) I was probably taking one or two more units than I really needed...I've really cut my snacking down and am noticing my "bolus" much more than before.
I did a fasting bolus test the other morning...I woke to 89, took my one Lantus dose...rose to about 144 (prior Lantus completely gone then)...then dropped and stayed at around 90for the next 4 hours until I had lunch...
That was a pretty "on the mark" bolus considering I had dropped my units over the last week or so.
That is one reason I like to take my Lantus in the morning...convenient fasting time to watch the start up action and the leveling out...tough to do at night.  | 
