Multiple IF Statements (IFS)

If someone could please tell me how I can get this to work it would be greatly appreciated. Thanks in advance!

IF
[DateTime_Out] >= "04-01-2018" AND [DateTime_Out] <= "03-31-2019" THEN "2018" ELSEIF

[DateTime_Out] >= "04-01-2019" AND [DateTime_Out] <= "03-31-2020" THEN "2019" ELSEIF

[DateTime_Out] >= "04-01-2020" AND [DateTime_Out] <= "03-31-2021" THEN "2020" ELSE
"ERROR"
ENDIF

Accepted answers

If your field is a date coming through the workflow the data type should be in the format of YYYY-MM-DD so the formula would look like this:

IF
[DateTime_Out] >= '2018-04-01' AND [DateTime_Out] <= '2019-03-31' THEN "2018" ELSEIF

[DateTime_Out] >= '2019-04-01' AND [DateTime_Out] <= '2020-03-31' THEN "2019" ELSEIF

[DateTime_Out] >= '2020-04-01' AND [DateTime_Out] <= '2021-03-31' THEN "2020" ELSE
"ERROR"
ENDIF

If your field is a date coming through the workflow the data type should be in the format of YYYY-MM-DD so the formula would look like this:

IF
[DateTime_Out] >= '2018-04-01' AND [DateTime_Out] <= '2019-03-31' THEN "2018" ELSEIF

[DateTime_Out] >= '2019-04-01' AND [DateTime_Out] <= '2020-03-31' THEN "2019" ELSEIF

[DateTime_Out] >= '2020-04-01' AND [DateTime_Out] <= '2021-03-31' THEN "2020" ELSE
"ERROR"
ENDIF

This works! Thanks!

My Question-

If col1 != ' ' and col2 != ' ' and col3 != ' ' and col4 != ' ' and col5 != ' ' then 'completed'

elseif col1 != ' ' and col2 != ' ' and col3 = ' ' and col4 = ' ' and col5 = ' ' then 'completed with 1 & 2'

elseif col1 != ' ' and col2 != ' ' and col3 != ' ' and col4 = ' ' and col5 = ' ' then 'completed with 1 & 2 & 3'

elseif col1 != ' ' and col2 != ' ' and col3 != ' ' and col4 != ' ' and col5 = ' ' then 'completed with 1 & 2 & 3 & 4'

else 'not completed'

Please help! Thanks in advance.