The POSTSTRATA statement names variables that form the poststrata to adjust the sampling weight for analyzing the survey.
The combinations of categories of POSTSTRATA variables define the poststrata in the sample.
The POSTSTRATA variables are one or more variables in the DATA= input data set. These variables can be either character or numeric. The formatted
values of the POSTSTRATA variables determine the categorical levels. Thus, you can use formats to group values into levels. See the FORMAT procedure in the
Base SAS Procedures Guide and the FORMAT statement and SAS formats in
SAS Formats and Informats: Reference for more information.
You must specify either poststratification totals or poststratification proportions, but not both, in the POSTSTRATA statement
after a slash (/).

PSTOTAL=SASdataset  values
POSTTOTAL=SASdataset  values
PSCONTROL=SASdataset  values

specifies an input data set that contains the poststratum totals or specifies the population poststratum totals as positive
values. The SURVEYMEANS procedure uses this information to compute weight adjustment for poststratification.
You can provide poststratification totals by specifying PSTOTAL=SASdataset, which names a SAS data set that contains the poststratification variables and the poststratum totals. This data set is called
the poststratum total data set.
A poststratum total data set must contain all the poststratification variables that are listed in the POSTSTRATA statement
and all the variables listed in the BY statement. If there are formats associated with the POSTSTRATA variables and the BY
variables, then the formats in the poststratum total data set for these variables must be consistent with those in the DATA=
data set in the PROC SURVEYMEANS statement.
A poststratum total data set must have a variable named _PSTOTAL_
that contains the poststratum totals. The value of _PSTOTAL_
must be positive.
When poststratum levels are easy to identify, their corresponding poststratum totals can be specified as a list of positive
numbers.
ORDER=FORMATTED
is used to order the levels of poststratum levels.
You can separate values in the PSTOTAL= option with blanks or commas. The number of values must equal the number of poststrata in the data. List the values in the order of the corresponding poststratum level. The sum of the values should equal the total sampling weights.

PSPCT=SASdataset  values
POSTPCT=SASdataset  values

specifies an input data set that contains the population poststratum proportions or specifies the population poststratum proportions
as positive values. The SURVEYMEANS procedure uses this information to compute weight adjustment for poststratification.
You can provide poststratification proportions by specifying POSTPCT=SASdataset, which names a SAS data set that contains the poststratification variables and the poststratum poststratification. This data
set is called the poststratum proportion data set.
A poststratum proportion data set must contain all the poststratification variables that are listed in the POSTSTRATA statement
and all the variables listed in the BY statement. If there are formats associated with the POSTSTRATA variables and the BY
variables, then the formats in the poststratum proportion data set for these variables must be consistent with those in the
DATA=
data set in the PROC SURVEYMEANS statement.
A poststratum proportion data set must have a variable named _PSPCT_
that contains the poststratum proportions. The value of _PSPCT_
must be positive.
You can provide poststratum proportions either as positive decimal numbers between 0 and 1 for all poststrata or as positive
percentages that must be less than 100 for all poststrata. If any value of the proportions is greater than 1, the procedure
treats all proportions as percentages instead of decimal numbers.
When poststratum levels are easy to identify, their corresponding poststratum proportions can be specified as a list of positive
numbers.
ORDER=FORMATTED
is used to order the levels of poststratum levels.
You can separate values in the POSTPCT= option with blanks or commas. The number of values must equal the number of poststrata in the data. List the values in the order of the corresponding poststratum level.
If you provide the proportions as decimal numbers, then the sum of these values over all poststrata must be 1.
If you provide the proportions as percentages, then the sum of these percentages over all poststrata must be 100.
You can also optionally specify the following option to create an output data set to store the poststratification weights.