Not sure of what you need, but maybe storing the desired value into a SAS macro variable may solve your problem.
proc sql noprint;
select mean(VALUE) into :MEAN_VALUE from DATA;
quit;
the into: statement will load a value into a SAS macro variable through SQL.
See the online doc here:
http://support.sas.com/documentation/cdl/en/mcrolref/61885/HTML/default/a000543554.htm
From there, you just need to reference the SAS macro variable in your program, then at runtime this will be substituted by the actual value loaded previously.
for example:
data _null_;
put "Mean value is: &MEAN_VALUE";
/* or */
MEAN=&MEAN_VALUE;
put MEAN=;
run;
Cheers from Portugal.
Daniel Santos @
www.cgd.pt