diff --git a/gromacs/force_lj.c b/gromacs/force_lj.c
index cdd6b82..9d7238f 100644
--- a/gromacs/force_lj.c
+++ b/gromacs/force_lj.c
@@ -83,6 +83,9 @@ double computeForceLJ_ref(Parameter *param, Atom *atom, Neighbor *neighbor, Stat
                             fix += delx * force;
                             fiy += dely * force;
                             fiz += delz * force;
+                            addStat(stats->atoms_within_cutoff, 1);
+                        } else {
+                            addStat(stats->atoms_outside_cutoff, 1);
                         }
                     }
                 }
@@ -93,8 +96,9 @@ double computeForceLJ_ref(Parameter *param, Atom *atom, Neighbor *neighbor, Stat
             }
         }
 
+        addStat(stats->calculated_forces, 1);
         addStat(stats->num_neighs, numneighs);
-        addStat(stats->force_iters, (numneighs + VECTOR_WIDTH - 1) / VECTOR_WIDTH);
+        addStat(stats->force_iters, (long long int)((double)numneighs * CLUSTER_DIM_M / CLUSTER_DIM_N));
     }
 
     LIKWID_MARKER_STOP("force");
@@ -250,7 +254,7 @@ double computeForceLJ_4xn(Parameter *param, Atom *atom, Neighbor *neighbor, Stat
 
         addStat(stats->calculated_forces, 1);
         addStat(stats->num_neighs, numneighs);
-        addStat(stats->force_iters, numneighs / 2);
+        addStat(stats->force_iters, (long long int)((double)numneighs * CLUSTER_DIM_M / CLUSTER_DIM_N));
     }
 
     LIKWID_MARKER_STOP("force");
diff --git a/gromacs/includes/stats.h b/gromacs/includes/stats.h
index 9c61788..4b08e3d 100644
--- a/gromacs/includes/stats.h
+++ b/gromacs/includes/stats.h
@@ -29,6 +29,8 @@ typedef struct {
     long long int calculated_forces;
     long long int num_neighs;
     long long int force_iters;
+    long long int atoms_within_cutoff;
+    long long int atoms_outside_cutoff;
 } Stats;
 
 void initStats(Stats *s);
diff --git a/gromacs/stats.c b/gromacs/stats.c
index 562a9fa..ccc6030 100644
--- a/gromacs/stats.c
+++ b/gromacs/stats.c
@@ -9,10 +9,13 @@ void initStats(Stats *s) {
     s->calculated_forces = 0;
     s->num_neighs = 0;
     s->force_iters = 0;
+    s->atoms_within_cutoff = 0;
+    s->atoms_outside_cutoff = 0;
 }
 
 void displayStatistics(Atom *atom, Parameter *param, Stats *stats, double *timer) {
 #ifdef COMPUTE_STATS
+
     const int MxN = CLUSTER_DIM_M * CLUSTER_DIM_N;
     double avg_atoms_cluster = (double)(atom->Nlocal) / (double)(atom->Nclusters_local);
     double force_useful_volume = 1e-9 * ( (double)(atom->Nlocal * (param->ntimes + 1)) * (sizeof(MD_FLOAT) * 6 + sizeof(int)) +
@@ -20,9 +23,11 @@ void displayStatistics(Atom *atom, Parameter *param, Stats *stats, double *timer
     double avg_neigh_atom = (stats->num_neighs * CLUSTER_DIM_N) / (double)(atom->Nlocal * (param->ntimes + 1));
     double avg_neigh_cluster = (double)(stats->num_neighs) / (double)(stats->calculated_forces);
     double avg_simd = stats->force_iters / (double)(atom->Nlocal * (param->ntimes + 1));
-#ifdef EXPLICIT_TYPES
+
+    #ifdef EXPLICIT_TYPES
     force_useful_volume += 1e-9 * (double)((atom->Nlocal * (param->ntimes + 1)) + stats->num_neighs) * sizeof(int);
-#endif
+    #endif
+
     printf("Statistics:\n");
     printf("\tVector width: %d, Processor frequency: %.4f GHz\n", VECTOR_WIDTH, param->proc_freq);
     printf("\tAverage atoms per cluster: %.4f\n", avg_atoms_cluster);
@@ -33,5 +38,11 @@ void displayStatistics(Atom *atom, Parameter *param, Stats *stats, double *timer
     printf("\tTotal number of SIMD iterations: %lld\n", stats->force_iters);
     printf("\tUseful read data volume for force computation: %.2fGB\n", force_useful_volume);
     printf("\tCycles/SIMD iteration: %.4f\n", timer[FORCE] * param->proc_freq * 1e9 / stats->force_iters);
+
+    #ifdef USE_REFERENCE_VERSION
+    const double eff_pct = (double)stats->atoms_within_cutoff / (double)(stats->atoms_within_cutoff + stats->atoms_outside_cutoff) * 100.0;
+    printf("\tAtoms within/outside cutoff radius: %lld/%lld (%.2f%%)\n", stats->atoms_within_cutoff, stats->atoms_outside_cutoff, eff_pct);
+    #endif
+
 #endif
 }