Hello, As an aspiring spread trader, I bought the "encyclopedia of commodity and financial spreads" from MRCI team and an other one from Courtney Smith. Both were good and I would like to thank JLaw for his advice because It greatly helped me understand the mechanics of spreads. However, the book from MRCI is from 2005 and I had the idea to do a "walk forward" test of their agricultural and meats spreads for 2006-2007-2008... The results were so bad that I only tested spreads beginning in Jan, Feb, Mar and Apr.It was enough...Something like 70% of losers and losers outstandingly bigger than winners... I know this book wasn't meant to be a trading system per se and that spreads must be chosen depending on current conditions, crops, demand ... but I still expected the list of spreads from the book to be just slightly positive as a whole... What happened in the past few years? Is it seasonality that didn't work or just MRCI's spreads? Thanks.