Based on date create new variable

[newbi]

Would someone be able to offer advice on how I can do the following:

Based on date_key i would like to create new column which can provide Sales start day (1st day of sale).  For example:

Date_KEY	RID	Sales
03/01/2014	1	$1000
03/02/2014	1	$1500
03/03/2014	1	$2000
03/05/2014	2	$1000
03/06/2014	3	$5000

Result i want:

Date_KEY	RID	Sales	Sales Start Day
03/01/2014	1	$1000	1
03/02/2014	1	$1500	2
03/03/2014	1	$2000	3
03/05/2014	2	$1000	1
03/06/2014	3	$5000	1

Thanks in advance.

[Linlin · Accepted solution]

data want;

set have; /* your dataset name */

by rid;

if first.rid then sales_start_day=0;

sales_start_day+1;

run;

[Quentin]

Hi,

Not sure I follow your logic, but I think below will make your WANT table:

data want;

  set have;

  by RID Date_Key;

  if first.RID then SalesStartDay=0;

  if first.Date_Key then SalesStartDay ++ 1;

run;

HTH

[newbi]

Thanks for all your help.

Linlin solutin worked:

data want;

set have; /* your dataset name */

by rid;

if first.rid then sales_start_day=0;

sales_start_day+1;

run;