From 84134106cbb84d697fa8a51469429d993ecd5e2b Mon Sep 17 00:00:00 2001
From: Damien Elmes <git@ichi2.net>
Date: Tue, 24 Apr 2012 04:35:36 +0900
Subject: [PATCH] derive period in review history graph from revlog, not
 collection crt

---
 anki/stats.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/anki/stats.py b/anki/stats.py
index 15badbaf6..24cf16ebd 100644
--- a/anki/stats.py
+++ b/anki/stats.py
@@ -251,7 +251,12 @@ group by day order by day""" % (self._limit(), lim),
         tot = totd[-1][1]
         period = self._periodDays()
         if not period:
-            period = first
+            # base off earliest repetition date
+            t = self.col.db.scalar("select id from revlog limit 1")
+            if not t:
+                period = 1
+            else:
+                period = (self.col.sched.dayCutoff - (t/1000)) / 86400
         i = []
         self._line(i, _("Days studied"),
                    _("<b>%(pct)d%%</b> (%(x)s of %(y)s)") % dict(