It has been pointed out that Excel has a 65K limit to rows.

Depending on the requirements you cold cut down the intervals, use multiple
columns or use access.

Access is quite easy to use in the simple sence and making an unlinked
database is just like a spreadsheet.

There is another text tool out that called PARSE which allows traversal of
text files and you can do quite powerful things with it. Do a search to find
it.