diff --git a/matlab/mcmc_ifac.m b/matlab/mcmc_ifac.m
index 38ed34ee90d80c952e071ac9d170dde2a477876d..34c68a4afab5e1ca3b424c688cb2b511e1865d22 100644
--- a/matlab/mcmc_ifac.m
+++ b/matlab/mcmc_ifac.m
@@ -29,7 +29,7 @@ function Ifac = mcmc_ifac(X, Nc)
 % You should have received a copy of the GNU General Public License
 % along with Dynare.  If not, see <http://www.gnu.org/licenses/>.
 
-Nc = min(Nc, length(X)/2);
+Nc = floor(min(Nc, length(X)/2));
 if mod(Nc,2),
     Nc=Nc-1;
 end