We show that on an n = 24m+ 8k-dimensional even unimodular lattice, if the shortest vector length is ≥ 2m, then as the number of vectors of length 2m decreases, the secrecy gain increases. We will also prove a similar result on general unimodular lattices. Furthermore, assuming the conjecture by Belfiore and Solé, we will calculate the difference between inverses of secrecy gains as the number ...