Assigning Continuous number to year and months

[Lindsey Buck]

Hi all,

I have date like this:

date
jan2015
jan2015
feb2015
march2015
march 2015
march2015

I want to create a variable that numbers them like this:

date
jan 2015 1
jan2015 1
feb2015 2
march2015 3
march2015 3
march2015 3

Can you help? Thanks!

[Andrew Musau]

If these are Stata year-month dates, then

egen wanted= group(date)

[Nick Cox]

As urged at FAQ Advice #12 using dataex is essential to clarify what kind of variables are being used. Data "like" this could be literal -- or not. You could have


(1) a string variable

(2) a numeric variable with value labels after a misguided encode (the worst of all worlds)

(3) a numeric monthly date with a date display format, as optimistically guessed by Andrew Musau.

I doubt the latter as (e.g.) jan2015 and march2015 would be using different display formats. If Andrew's guess at (3) is right, fine, but otherwise please follow https://www.statalist.org/forums/help#stata and use dataex to show us what you have.