Countif Within A Range

[Vancouver]

Hi All,

The below formula gives me a count of all values in Column B that are between the range of Column C and Column D but I would also like to be able to copy this formula down so that it doesn't count the maximum of the previous row (minimum of the current row) thus avoiding a double count.

For example, I want the formula to count $500 in Column B in the range of C2 to D2 but I want the formula to exclude $500 in Column B in the range of C3 and D3.

=COUNTIF($B$2:$B$20,">="&$C2)-COUNTIF($B$2:$B$20,">"&$D2)

I would ideally like to use this date to create a histogram.

Thanks in advance for the input!

Thanks,

Mario