MPL Documentation

DOWNTO

The for statement causes the statement after do to be executed once for each value in the range first to last. Downto is used when counting down.
var
   A:LongInt;

Begin
   For A:=100 downto 10 do
      if A mod 30=0 then writeln(A);
End.
Output:
30
Source: Reserved Words
See Also:
mod, for, do.