One set up which could deliver it here ..

Assume source data/formulas in cols A to D starts in row2 down

Since it's going to be calc intensive, set the calc mode to Manual.
Click Tools Options Calculation tab Check "Manual" OK

Enter the col labels in G1:L1 :
Part#, 1-30, 31-60, 61-90, 91-120, 120

Put in F2:
=IF(A2="","",IF(COUNTIF($A$2:A2,A2)1,"",ROW()))
Copy F2 down to cover the max expected extent of data, say down to F55500.
Leave F1 empty. Hide away col F.

Put in G2:
=IF(ROW(A1)COUNT(F:F),"",INDEX(A:A,SMALL(F:F,ROW( A1))))
Copy G2 down by the smallest extent sufficient to cover the max expected
number of unique Part#s, say down to G1000. Col G will dynamically extract
the list of unique Part#s, all neatly bunched at the top

Then place

In H2:
=IF($G2="","",SUMPRODUCT(($A$2:$A$55500=$G2)*($D$2 :$D$55500=1)*($D$2:$D$55500<=30)))

In I2:
=IF($G2="","",SUMPRODUCT(($A$2:$A$55500=$G2)*($D$2 :$D$55500=31)*($D$2:$D$55500<=60)))

In J2:
=IF($G2="","",SUMPRODUCT(($A$2:$A$55500=$G2)*($D$2 :$D$55500=61)*($D$2:$D$55500<=90)))

In K2:
=IF($G2="","",SUMPRODUCT(($A$2:$A$55500=$G2)*($D$2 :$D$55500=91)*($D$2:$D$55500<=120)))

In L2:
=IF($G2="","",SUMPRODUCT(($A$2:$A$55500=$G2)*($D$2 :$D$55500=120)))

Copy H2:L2 down to L1000 (consistent with col G's fill)

If desired, switch off zeros display in the sheet for a neater look:
Click Tools Options View tab Uncheck "Zero values" OK

Cols G to L will provide the required summary. Press F9 to recalc, but only
whenever necessary (eg: after completing new data entries for the day). Adapt
to suit ..
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"Tiziano" wrote:
I have a worksheet with about 55,000 line items in it regarding sales
history for the past nine months.
* Column A has part numbers. (The same part number can appear multiple
times)
* Column B has the date the order for the part number was received.
* Column C has the date the ordered part number shipped.
* Column D has the number of days elapsed between cols. B and C.

What I would like to do is summarize all this data such that:
* One column lists all the part numbers. (No duplicates!)
* For each part number, I'd like to know how many times the order shipped
within 1-30 days, 31-60 days, 61-90 days, 91-120 days, more than 120 days.

Can anybody help with an Excel formula?

Thanks.
--
Tiziano