Here is a little code with the SASHELP.CLASS dataset. Does it look like what you want to do ? If so, just use the same idea, replacing the "1" values in the new variables by SLAB_TON.
[pre]
DATA work.class ;
SET sashelp.class ;
IF sex="F" THEN sexF = 1 ;
ELSE sexM = 1 ;
RUN ;
PROC FORMAT ;
VALUE ages
LOW - 14 = "14 -"
OTHER = "15 +" ;
VALUE weights
LOW - 100 = "<100 lb"
OTHER = ">100 lb" ;
RUN ;
PROC TABULATE DATA = work.class F= 7. ;
CLASS age weight ;
VAR sexF sexM ;
FORMAT age ages. weight weights. ;
TABLE weight,
(sexM="# boys"*age=""*SUM="" sexF="# girls"*SUM="") ;
RUN ;