diff --git a/jass_preprocessing/compute_score.py b/jass_preprocessing/compute_score.py
index c275ceb98c14de00036a6f12148aa5a6ffe2105c..fd176a381082aa0ee3c2b88b6123fade5d73a5e9 100644
--- a/jass_preprocessing/compute_score.py
+++ b/jass_preprocessing/compute_score.py
@@ -51,7 +51,7 @@ def compute_sample_size(mgwas, diagnostic_folder, trait, perSS = 0.7):
         warnings.warn("Some snp had an infinite sample size")
 
     myW_thres = np.percentile(myN.dropna(), 90)
-    ss_thres = int(perSS) * myW_thres
+    ss_thres = float(perSS) * myW_thres
     mgwas["computed_N"] = myN
     plt.clf()
     p1 = sns.distplot(mgwas.computed_N[~mgwas.computed_N.isna()])