CHAPTER Ⅰ．INTRODUCTION 1
Sketch a,Smoothing lines and cycle． 2
Table A,San Francisco real estate activity 1920 to 1929．The annual cycle． 4
Chart 1,San Francisco real estate activity 1920 to 1929．Application of moving average and trend;the annual cycle． 7
The plan of procedure． 8
A simplified freehand procedure with no objective checks． 8
CHAPTER Ⅱ．THE SMOOTHING LINES 10
Section 1:Locating Smoothing Line A 10
Section 2:Devices to Aid the Smoothing process 11
Moving Averages 11
Sketch b,Dotted ends of moving average line． 12
The moving cyclical average． 13
Sketch c,Correct and incorrect lengths for moving average． 14
Sketch d,Tentative smoothing line and phase points． 14
Sketch d2,same,with extended time scale． 14
Tentative Smoothing line and phase points． 15
Section 3:Locating Smoothing Line B 16
Table B,A suggested arrangement of the calculations for locating the smoothing lines． 18
The moving geometric mean． 19
Section 4:Locating Smoothing Line M 19
Sketch e,Correcting for curvature． 20
Curvature:A systematic error in moving averages;its correction by reiteration of the moving average． 21
Use of Smoothing Line M as a guide to a mathematically fitted trend． 22
Section 5:Illustration:San Francisco real estate activity,1867 to 1940;two stages of smoothing． 22
Table Ca,Locating SL B． 25
Table Cb,Locating SL M;first part of calculation． 28
Table Cc,Locating SL M,continued,correction for curvature． 31
Chart 2,San Francisco real estate activity,1867 to 1940;first stage of smoothing． 32
Chart 3,San Francisco real estate activity,second stage of smoothing． 33
CHAPTER Ⅲ．THE CYCLES 34
Section 1:Characteristics of the cycles 34
Measures of the annual cycle． 34
Measures of the short business cycle． 35
Measures of the major cycle． 35
Table D;Arrangement for the calculation of the measures of the several orders of cycles． 36
Da,The seasonal or annual cycle． 36
Db,The short business cycle． 37
Dc,The major cycle． 38
Explanation of a use of straight lines． 39
Section 2:Illustration:San Francisco real estate activity;Calculation of the measures of the cycles,from the record 1867 to 1940． 39
Table Ea,Measures of the short business cycle． 40
Table Eb,Measures of the Major cycle． 42
Chart 4,Cycles based on the record 1867 to 1940． 44
Chart 5,Standard or typical cycles based on the record 1867 to 1940． 45
CHAPTER Ⅳ．APPLICATION TO CORRELATION AND FORECASTING 46
Section 1:Comparison of time series;correlation 46
Section 2:Forecasting 46
San Francisco real estate activity based on the record 1867 to 1940． 47
Chart 6,A forecast． 50
CHAPTER Ⅴ．ANALYSIS OF SEVEN SERIES 51
Section 1:Wheat prices 52
Table F 54
Charts 7,8,9,10 59
Table G 63
Section 2:Wheat production 66
Table H 68
Charts 11,12,13,14,15 75
Table J 80
Section 3:Cotton production 83
Table K 85
Charts 16,17,18,19 90
Table L 94
Section 4:Crude petroleum output 97
Table M 99
Charts 20,21,22,23 104
Section 5:Pig iron production 111
Table P 113
Charts 24,25,26,27 120
Table Q 124
Section 6:Portland cement production 127
Table R 129
Charts 28,29,30 132
Section 7:Erie Canal freight 138
Table T 141
Charts 31,32,33,34 146
Table U 150