diff --git a/seinflux.py b/seinflux.py
index b900ee2..7c04e48 100644
--- a/seinflux.py
+++ b/seinflux.py
@@ -342,7 +342,7 @@ class SEHistory(InfluxDBWrapper):
                         if chunks:
                             prevbeg, prevend = chunks[-1]
                             # merge when joining or started at the same day
-                            merge = prevend + gap < ts or sameday(prevbeg, ts)
+                            merge = prevend + gap > ts or sameday(prevbeg, ts)
                         else:
                             merge = False
                         if merge: