Reports For Counting:

Reports For Counting:
Standard summary report show every row in database.Reports for counting show only unique rows.
Create a formula field on which object you want to count for example you want to count on opportunities create a formula field number of opportunities return type number make sure decimal places to 0 and enter 1 in the formula editor section.Next step create a report add this field and summarize it as shown below.

You can observe total number of accounts ,total number of opportunities and total number opportunities per each account.Further you can create custom summary formula to calculate record ratios.To achieve this you need to create formula field on account like you did on opportunity.Next create a custom summary formula on your report double click on add formula from your field panel it opens custom summary formula window.

Report capability can be improved by bucketing.

Create a formula field as of your condition to display in report.For example
IF(amount>2000000,"Highly Qulaified",IF(amount>1000000&&amount<2000000,"Qualified"),"Under Qualified").Summarize your report with this custom formula field and observe on your dashboard