Total Count of Items in a List in Sharepoint 2007

I had a recent assignment to test the performance of a List. The list was behaving really slow and I need to determine the total number of items in the list.
Aaaah ………… there starts the problem. I wanted the total number of items in the list and I could only do that by navigating through the List Item pages which was around 20,000 + Items, So need to click through every single pages and it would take couple of months to figure out the exact numbers. Then I thought about the "Calculated Columns" in Sharepoint.
Finally I figured out to get the total count of the Items in a Sharepoint List. Here are the steps -
Step 1.
Create a "Calculated (calculation based on other columns) " column in the List
Step 2.
Column Name - "Total"
The Type of Information in this column - "Calculated"
In the Formula Column put - "=SUM(ID)" (without apostrophise)
Select "The data type returned from this formula is: " as Number
Step 3.
Select "OK" - a new column will be added to the List and then you could see the Column "Total" which would display values from 1 to End number in ascending order. If you click the header "Total" the list would be displayed in descending order displaying the Total number of the Items in the list.