diff --git a/simplecoin/config.py b/simplecoin/config.py
index 4a52e026..22726c4c 100644
--- a/simplecoin/config.py
+++ b/simplecoin/config.py
@@ -482,19 +482,7 @@ def calc_shares(self, block_payout):
 class PropChain(Chain):
     def calc_shares(self, block_payout):
         assert block_payout.chainid == self.id
-        curr_block = block_payout.block
-        last_block = (m.Block.query.filter_by(algo=curr_block.algo,
-                                              merged=curr_block.merged,
-                                              currency=curr_block.currency).
-                      filter(m.Block.hash != curr_block.hash).
-                      order_by(m.Block.found_at.desc())).first()
-        stop_slice = 0
-        if last_block:
-            bps = [bp for bp in last_block.chain_payouts if bp.chainid == self.id]
-            if len(bps) > 0:
-                last_block_payout = bps[0]
-                stop_slice = last_block_payout.solve_slice
-        return self._calc_shares(block_payout.solve_slice, stop_slice=stop_slice)
+        return self._calc_shares(block_payout.solve_slice, stop_slice=block_payout.start_slice)
 
 
 class ChainKeeper(Keeper):
diff --git a/simplecoin/models.py b/simplecoin/models.py
index 79451118..5f9fa47e 100755
--- a/simplecoin/models.py
+++ b/simplecoin/models.py
@@ -135,6 +135,7 @@ class ChainPayout(base):
     chainid = db.Column(db.Integer, primary_key=True)
     block_id = db.Column(db.Integer, db.ForeignKey('block.id'), primary_key=True)
     block = db.relationship('Block', foreign_keys=[block_id], backref='chain_payouts')
+    start_slice = db.Column(db.Integer)
     # Placeholder for the point at which the block was solved in this share chain.
     solve_slice = db.Column(db.Integer)
     # Shares on this chain. Used to get portion of total block
diff --git a/simplecoin/scheduler.py b/simplecoin/scheduler.py
index 64ba2b07..69b6f063 100644
--- a/simplecoin/scheduler.py
+++ b/simplecoin/scheduler.py
@@ -561,6 +561,8 @@ def credit_block(redis_key, simulate=False):
                 value = Decimal(value)
             elif key == "solve_index":
                 value = int(value)
+            elif key == "start_index":
+                value = int(value)
             # XXX: Could do extra check for setting duplicate data (overrite) here
             chain[key] = value
 
@@ -569,8 +571,10 @@ def credit_block(redis_key, simulate=False):
     for id, chain in chain_data.iteritems():
         if chain['shares'] == 0:
             continue
+        start_slice = chain['start_index'] if chain.has_key('start_index') else chain['solve_index'] - 1
         cpo = ChainPayout(chainid=id,
                           block=block,
+                          start_slice=start_slice,
                           solve_slice=chain['solve_index'],
                           chain_shares=chain['shares'])
         cpo.user_shares = {}