Show null values as blank cells

[RICKDM]

I have a data table with "date" in column A and data in column D. For every date, I have 20 data readings, so 20 rows in my table are dedicated to each date, beginning in A2. I want to average this data in a summary table, with "date" in column M and "daily average" in column N, with the first date beginning in cell M12. So for every 20 rows in my data table, I want 1 row in my summary table. I have used the following function in my summary table to grab the "date" I input into my data table:

=INDEX($A:$A,(ROW($A3)-1)*20+2)

And it works, but the dates that I have not yet entered (future dates 8/24/2011, etc.) show up as 1/0/1900 instead of a blank cell. Is there something I can add to this function in order for the future dates to show up as blank cells, and when I add future data, the dates are reflected in my summary table?

 

[T. Valko]

I have a data table with "date" in column A and data in column D. For every date, I have 20 data readings, so 20 rows in my table are dedicated to each date, beginning in A2. I want to average this data in a summary table, with "date" in column M and "daily average" in column N, with the first date beginning in cell M12. So for every 20 rows in my data table, I want 1 row in my summary table. I have used the following function in my summary table to grab the "date" I input into my data table:

=INDEX($A:$A,(ROW($A3)-1)*20+2)

And it works, but the dates that I have not yet entered (future dates 8/24/2011, etc.) show up as 1/0/1900 instead of a blank cell. Is there something I can add to this function in order for the future dates to show up as blank cells, and when I add future data, the dates are reflected in my summary table?

Try this...

=IF(INDEX($A:$A,(ROW($A3)-1)*20+2)=0,"",INDEX($A:$A,(ROW($A3)-1)*20+2))