diff --git a/modules/yomoni/browser.py b/modules/yomoni/browser.py
index c9e86972d9ae81d9553c8b983254a46ae1b420d1..b405e840e4ad54e7a30b99e2c57386e1f24aeba3 100644
--- a/modules/yomoni/browser.py
+++ b/modules/yomoni/browser.py
@@ -143,7 +143,9 @@ def iter_investment(self, account, invs=None):
                 i.unitvalue = CleanDecimal().filter(inv['valeurCotation'])
                 i.valuation = CleanDecimal().filter(inv['montantEuro'])
                 i.vdate = Date().filter(inv['datePosition'])
-                i.diff = CleanDecimal().filter(inv['performanceEuro'])
+                # performanceEuro is null sometimes in the JSON we retrieve.
+                if inv['performanceEuro']:
+                    i.diff = CleanDecimal().filter(inv['performanceEuro'])
 
                 self.investments[account.id].append(i)
         return self.investments[account.id]