This book is a thorough study of the performance of Dow Theory signals since its inception in 1897. The Theory is explained and analyzed and compared to a procedure developed by John Magee mid-twentyth century. John Magee was a prominent analyst and author who co-authored the foundation work of technical analysis, Technical Analysis of Stock Trends, now in its 10th Edition as edited and coauthored by W.H.C. Bassetti.