The aforementioned browsers follow the ECMA standard and will return a value of 2000. The following code can be modified to suit your application or used as is if you want a personal hit counter. There is a nice symmetry to this code. The setCookie lines are necessary in order to update both the cookie values if they have changed and the expiry date. The cookies would eventually expire without these lines.
Some browsers have difficulties recognising cookie strings as numbers.
The second option will crash in Internet Explorer if headCount is not a valid number. Notice also that the use of the bikky variable is removed from the main body of code. A number of people have asked about setting cookies that can be read from different frames or sections of the site. A cookie set in a subdirectory will not overwrite a cookie set in its parent directory but will hide its value.