[R] Alter character attribute

[LCOG1]

Hi everyone

I have some records that include a date attribute for the date and time but
i need to separate the data and analyze it separately in GIS by Month and
Year, so i need to pull these attributes out and create their own attribute
field.  

So the input:
RawData2.. returns

  ID   period_end_date
1 22 9/10/2007 0:00:00
2 44  2/2/2006 0:00:00

and i need to get 
  ID   period_end_date    Month Year
 22 9/10/2007 0:00:00   9         2007
 44  2/2/2006 0:00:00    2        2006

The below gets me this in list form which i can then add back into the
initial data frame BUT
i have over 4.5 million records and when i run the below it ran for more
than 18 hours and only go through about 2.7 millions records when i gave up
and ended the process.  

So how can i make this more efficient and possibly add the new attributes
(month/year) to the data frame on the fly.

Thanks guys....

#Create sample data
RawData2..<-data.frame(ID=c(22,44),period_end_date=c("9/10/2007
0:00:00","2/2/2006 0:00:00"))

#Create lists to store month and year results
Data.Month_<-list()
Data.Year_<-list()
#pull out year/month attribute at put in own column
for(i in 1:length(RawData2..$ID)){
     #Select Record
     Data.X<-RawData..[i,]
     #Separate date into month, day, and year 
     DateSplit<-strsplit(Data.X$period_end_date,"/")
     #Select month
     Month<-unlist(DateSplit)[1]
     #Separate year from time attribute
     Year.X<-strsplit(unlist(DateSplit)[3]," ")
     Year.Y<-unlist(Year.X)[1]
     Data.Month_[[i]]<-Month
     Data.Year_[[i]]<-Year.Y

}


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