If you want to try Glenn's suggestion of a PivotTable, you'll find that it has an option to display the values with the top 5 counts. If you're not familiar with PivotTables, you may find the instructions below to be helpful.
Creating a PivotTable can be somewhat challenging because of the unfamiliar nature of the wizard. To create a PivotTable:
1) Make sure that each column has a heading label, then select any point within your data. I'll assume that you have labelled your data "MyData"
2) Open the Data...PivotTable and PivotChart Report menu item
3) Click Finish in the resulting wizard. This will create a PivotTable on a new worksheet. Or you can click "Next" twice and choose to put the PivotTable in the existing worksheet in step 3 of the wizard. You'll then need to pick the top left cell of that report.
The tricky part come next. You will be presented with a blank PivotTable with big labels for the type of data required in each section. You need to drag named fields from the "PivotTable field list" dialog onto the PivotTable.
4) Drag the "MyData" field label into the "Drag Row Items Here" field
5) Drag the "MyData" field label into the "Drag Data Items Here" field
6) Right-click one of the cells in the first column of your PivotTable and choose "Field settings" from the resulting pop-up.
7) Choose to summarize by "Count" instead of "Sum"
8) Click the "Advanced" button
9) Choose the option to display the "Top 10". Then choose 5 in the dropdown field below that option, and "Count of MyData" in the other dropdown at the bottom right.
10) Choose to sort the data in Descending order, then specify "Count of MyData" in the dropdown field underneath that option.
You now have a PivotTable showing the counts of the five most frequent numbers in your original data.
Brad