How can i generate series base on this Format
0000-00-0000
0000 = series number
00 = Month
0000 = year
How can i generate series base on this Format
0000-00-0000
0000 = series number
00 = Month
0000 = year
R
A long-winded way to create a serial number per month is to put this "seed value" in cell F2 (assuming F1 is your header):
'0001-01-2021
then put this in F3:
=TEXT(VALUE(LEFT(F2,4))+1,"0000-") & IF(MOD(ROW()-1,13)=0,"01-"&RIGHT(F2,4)+1, TEXT(MOD(ROW()-1,13),"00") & "-" & RIGHT(F2,4))
(or change F2 in bold to suit). The combination of IF with MOD function (where the divisor is 13) means every 13th month, the middle "00" (within 0000-00-0000) will reset to 01 and the year will go up by one. Otherwise, the serial number goes up one, as does the month.
Copy this down and you'll get a series like:
Serial number
0001-01-2021
0002-02-2021
0003-03-2021
0004-04-2021
0005-05-2021
0006-06-2021
0007-07-2021
0008-08-2021
0009-09-2021
0010-10-2021
0011-11-2021
0012-12-2021
0013-01-2022
0014-01-2022
0015-02-2022
0016-03-2022
0017-04-2022
0018-05-2022
0019-06-2022
0020-07-2022
0021-08-2022
0022-09-2022
0023-10-2022
0024-11-2022
0025-12-2022
0026-01-2023
0027-01-2023
If your seed valiue doesn't have 01 in the middle, you will need to change the bold bit of ROW()-1 e.g. if the seed is 0001-05-2022 say, then the formula in F2 will need to have ROW()+3 in two places.
If you have Excel 365, you could look at Don's video tutorial here SEQUENCE() Function for Power List Making in Excel 365 and try to create something more sophisticated.
Hope this helps.