Author: Oscar Cronquist Article last updated on January 16, 2018

Introduction

What are unique distinct values?

Unique distinct values are all values but duplicates are merged into one value.

Count unique distinct values within same week

Formula in B3:

=WEEKNUM(C3) + ENTER

Array formula in E3:

=SUM(--((FREQUENCY(IF(YEAR(C3)&"-"&B3=YEAR($C$3:$C$11)&"-"&$B$3:$B$11, Item, ""), Item))>0))

How to create an array formula

  1. Copy (Ctrl + c) and paste (Ctrl + v) array formula into formula bar.
  2. Press and hold Ctrl + Shift.
  3. Press Enter once.
  4. Release all keys.

Copy cell E3 and paste it down as far as needed.

Explaining array formula in cell E3

=SUM(--((FREQUENCY(IF(YEAR(C3)&"-"&B3=YEAR($C$3:$C$11)&"-"&$B$3:$B$11, Item, ""), Item))>0))

Step 1 - Filter records in date range

=SUM(--((FREQUENCY(IF(YEAR(C3)&"-"&B3=YEAR($C$3:$C$11)&"-"&$B$3:$B$11, Item, ""), Item))>0))

IF(YEAR(C3)&"-"&B3=YEAR($C$3:$C$11)&"-"&$B$3:$B$11, Item, "")

becomes

IF("2010-2"={"2010-2";"2010-2";"2010-2";"2010-2";"2011-3";"2010-3";"2010-3";"2010-3";"2010-3"}, Item, "")

becomes

IF({TRUE;TRUE;TRUE;TRUE;FALSE;FALSE;FALSE;FALSE;FALSE}, {1150; 1150; 1131; 1131; 1126; 1151; 1150; 1131; 1131}, "")

and returns

{1150;1150;1131;1131;"";"";"";"";""}

Step 2 - Calculate frequency

=SUM(--((FREQUENCY(IF(YEAR(C3)&"-"&B3=YEAR($C$3:$C$11)&"-"&$B$3:$B$11, Item, ""), Item))>0))

FREQUENCY(IF(YEAR(C3)&"-"&B3=YEAR($C$3:$C$11)&"-"&$B$3:$B$11, Item, ""), Item))

becomes

FREQUENCY({1150;1150;1131;1131;"";"";"";"";""}, {1150; 1150; 1131; 1131; 1126; 1151; 1150; 1131; 1131}))

and returns

{2;0;2;0;0;0;0;0;0;0}

Step 3 - Count and sum values larger than 0 (zero)

=SUM(--((FREQUENCY(IF(YEAR(C3)&"-"&B3=YEAR($C$3:$C$11)&"-"&$B$3:$B$11, Item, ""), Item))>0))

becomes

=SUM(--(({2;0;2;0;0;0;0;0;0;0})>0))

becomes

=SUM(--({TRUE; FALSE; TRUE; FALSE; FALSE; FALSE; FALSE; FALSE; FALSE; FALSE}))

becomes

=SUM({1;0;1;0;0;0;0;0;0;0})

and returns 2 in cell E3.

Count unique distinct values within same month

Array formula in E16:

=SUM(--(FREQUENCY(IF(YEAR(C16)&"-"&MONTH(C16)=YEAR($C$16:$C$24)&"-"&MONTH($C$16:$C$24), $D$16:$D$24, ""), ($D$16:$D$24))>0))

How to create an array formula

  1. Copy (Ctrl + c) and paste (Ctrl + v) array formula into formula bar.
  2. Press and hold Ctrl + Shift.
  3. Press Enter once.
  4. Release all keys.

Copy cell E16 and paste it down as far as needed.

Count unique distinct values within same year

Array formula in E29:

=SUM(--(FREQUENCY(IF(YEAR(C29)=YEAR($C$29:$C$37), $D$29:$D$37, ""), ($D$29:$D$37))>0))

How to create an array formula

  1. Copy (Ctrl + c) and paste (Ctrl + v) array formula into formula bar.
  2. Press and hold Ctrl + Shift.
  3. Press Enter once.
  4. Release all keys.

Copy cell E29 and paste it down as far as needed.

Download excel sample file

Count-unique-occurences-within-same-week-month-year.xls

(Excel 97-2003 Workbook *.xls)

Functions in this article:

IF(logical_test;[value_if:true];[value_if_false]) Checks whether a condition is met, and returns one value if TRUE, and another value if FALSE

SUM(number1,[number2],)
Adds all the numbers in a range of cells

COUNTIF(range,criteria)
Counts the number of cells within a range that meet the given condition

FREQUENCY(data_array, bins_array)
Calculates how often values occur within a range of values and then returns a vertical array of numbers having one more element than Bins_array.