For an arbitrary rational lattice L with gain gamma, the average numbe
r of states (respectively, branches) in any given trellis diagram of L
is bounded below by a function of gamma, It is proved that this funct
ion grows exponentially in gamma, In the reverse direction, it is prov
ed that given epsilon > 0, for arbitrarily large values of gamma, ther
e exist lattices of gain gamma with an average number of branches and
states less than exp (gamma((1+epsilon))).