diff --git a/lib/mtgox/client.rb b/lib/mtgox/client.rb
index <HASH>..<HASH> 100644
--- a/lib/mtgox/client.rb
+++ b/lib/mtgox/client.rb
@@ -33,10 +33,10 @@ module MtGox
     #   offers.bids[0, 3]
     def offers
       offers = get('/code/data/getDepth.php')
-      offers['asks'] = offers['asks'].sort_by{|ask| ask[0].to_f}.map do |ask|
+      offers['asks'].sort_by!{|ask| ask[0].to_f}.map! do |ask|
         Ask.new(*ask)
       end
-      offers['bids'] = offers['bids'].sort_by{|bid| bid[0].to_f}.reverse.map do |bid|
+      offers['bids'].sort_by!{|bid| bid[0].to_f}.reverse!.map! do |bid|
         Bid.new(*bid)
       end
       offers
Don't waste memory by duplicating objects