diff --git a/tests/pipeline/test_us_equity_pricing_loader.py b/tests/pipeline/test_us_equity_pricing_loader.py
index b75f4799..a10ea0fb 100644
--- a/tests/pipeline/test_us_equity_pricing_loader.py
+++ b/tests/pipeline/test_us_equity_pricing_loader.py
@@ -175,43 +175,43 @@ DIVIDENDS = DataFrame(
     [
         # Before query range, should be excluded.
         {'declared_date': Timestamp('2015-05-01', tz='UTC').to_datetime64(),
-         'ex_date': Timestamp('2015-06-02', tz='UTC').to_datetime64(),
+         'ex_date': Timestamp('2015-06-01', tz='UTC').to_datetime64(),
          'record_date': Timestamp('2015-06-03', tz='UTC').to_datetime64(),
          'pay_date': Timestamp('2015-06-05', tz='UTC').to_datetime64(),
          'amount': 90.0,
          'sid': 1},
         # First day of query range, should be excluded.
         {'declared_date': Timestamp('2015-06-01', tz='UTC').to_datetime64(),
-         'ex_date': Timestamp('2015-06-11', tz='UTC').to_datetime64(),
+         'ex_date': Timestamp('2015-06-10', tz='UTC').to_datetime64(),
          'record_date': Timestamp('2015-06-15', tz='UTC').to_datetime64(),
          'pay_date': Timestamp('2015-06-17', tz='UTC').to_datetime64(),
          'amount': 80.0,
          'sid': 3},
         # Third day of query range, should have last_row of 2
         {'declared_date': Timestamp('2015-06-01', tz='UTC').to_datetime64(),
-         'ex_date': Timestamp('2015-06-15', tz='UTC').to_datetime64(),
-         'record_date': Timestamp('2015-06-16', tz='UTC').to_datetime64(),
+         'ex_date': Timestamp('2015-06-12', tz='UTC').to_datetime64(),
+         'record_date': Timestamp('2015-06-15', tz='UTC').to_datetime64(),
          'pay_date': Timestamp('2015-06-17', tz='UTC').to_datetime64(),
          'amount': 70.0,
          'sid': 3},
         # After query range, should be excluded.
         {'declared_date': Timestamp('2015-06-01', tz='UTC').to_datetime64(),
-         'ex_date': Timestamp('2015-06-26', tz='UTC').to_datetime64(),
+         'ex_date': Timestamp('2015-06-25', tz='UTC').to_datetime64(),
          'record_date': Timestamp('2015-06-28', tz='UTC').to_datetime64(),
          'pay_date': Timestamp('2015-06-30', tz='UTC').to_datetime64(),
          'amount': 60.0,
          'sid': 6},
         # Another action in query range, should have last_row of 3
         {'declared_date': Timestamp('2015-06-01', tz='UTC').to_datetime64(),
-         'ex_date': Timestamp('2015-06-16', tz='UTC').to_datetime64(),
+         'ex_date': Timestamp('2015-06-15', tz='UTC').to_datetime64(),
          'record_date': Timestamp('2015-06-18', tz='UTC').to_datetime64(),
          'pay_date': Timestamp('2015-06-20', tz='UTC').to_datetime64(),
          'amount': 50.0,
          'sid': 3},
         # Last day of range.  Should have last_row of 7
         {'declared_date': Timestamp('2015-06-01', tz='UTC').to_datetime64(),
-         'ex_date': Timestamp('2015-06-22', tz='UTC').to_datetime64(),
-         'record_date': Timestamp('2015-06-23', tz='UTC').to_datetime64(),
+         'ex_date': Timestamp('2015-06-19', tz='UTC').to_datetime64(),
+         'record_date': Timestamp('2015-06-22', tz='UTC').to_datetime64(),
          'pay_date': Timestamp('2015-06-30', tz='UTC').to_datetime64(),
          'amount': 40.0,
          'sid': 3},
diff --git a/zipline/data/us_equity_pricing.py b/zipline/data/us_equity_pricing.py
index 57718438..0d308c75 100644
--- a/zipline/data/us_equity_pricing.py
+++ b/zipline/data/us_equity_pricing.py
@@ -654,15 +654,15 @@ class SQLiteAdjustmentWriter(object):
             sid = sids[i]
             ex_date = ex_dates[i]
             day_loc = calendar.get_loc(ex_date)
-            div_adj_date = calendar[day_loc - 1]
+            prev_close_date = calendar[day_loc - 1]
             try:
                 prev_close = daily_bar_reader.spot_price(
-                    sid, div_adj_date, 'close')
+                    sid, prev_close_date, 'close')
                 if prev_close != 0.0:
                     ratio = 1.0 - amount / prev_close
                     ratios[i] = ratio
                     # only assign effective_date when data is found
-                    effective_dates[i] = div_adj_date.value
+                    effective_dates[i] = ex_date
             except NoDataOnDate:
                 logger.warn("Couldn't compute ratio for dividend %s" % {
                     'sid': sid,