Date format Issues

I have this bit of code, the date difference seem to be calculating 19 days, no matter what date I put in month of October or November in the datestamp field!!!

If the datestamp field is in September it calculates correctly!!!

I need to know how many days (not broken into months and days, a simple qty of days!!)
What am I doing wrong!!!


Dim mStrDte As String, mStrDte_tics As Long
Dim datestamp As String, datestamp_tics As Long
Dim meptme As Long

DateTime.DateFormat = "mm/dd/yyyy"
datestamp = "10/30/2012"
datestamp_tics = DateTime.DateParse(datestamp)

mStrDte = "09/11/2012"
DateTime.DateFormat = "mm/dd/yyyy"
mStrDte_tics = DateTime.DateParse(mStrDte)


'Calculate days
meptme = ((datestamp_tics - mStrDte_tics))/DateTime.TicksPerDay