You can enable it with scripting. Example directly from Scripting Index for EWMA
Names Default To Here(1);
dt = Open("$SAMPLE_DATA/Quality Control/Clips1.jmp");
dt << Select Rows({31, 32, 33, 34, 35, 36, 37, 38, 39, 40}) <<
exclude << hide;
obj = dt << EWMA Control Chart(
Y(:Gap),
Subgroup(:Sample),
Show Excluded Region(0)
);
-Jarmo