Project Code AppleScript.applescript

set thePList to "Users:JoeBuhlig:Dropbox:pList:Project_Codes.plist"
set thePListPath to POSIX path of thePList
tell application "System Events"
	tell property list file thePListPath
		tell contents
			set pcode to value of property list item "HouseCar"
			set yr to text -2 thru -1 of ("00" & (year of (current date))) as number
			set y to text -6 thru -5 of pcode as number
			set inc to text -2 thru -1 of pcode as number
			if (yr > y) then
				set inc to 1
			else
				set inc to inc + 1
			end if
			set inc to text -2 thru -1 of ("00" & inc)
			set newcode to yr & "HC" & inc as string
			set value of property list item "HouseCar" to newcode
		end tell
	end tell
end tell
return newcode