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Models for seasonal adjustment of TSI data inputs

Mode Model(1) Trading days(2) and holidays(3) Outliers(4) ARIMA
Rail        
Rail Passenger A No TD; Easter[7], Thanksgiving_7 No significant outliers (0,1,1)(0,1,1)
Rail Freight        
Carloads A No TD; Leap year LS DEC2008 (0,1,1)(0,1,1)
Intermodals M No TD; Leap year; Easter[7], Memorial Day, Thanksgiving_8, Christmas AO OCT2002; LS DEC2008 (0,1,1)(0,1,1)
Trucking A TD; No holidays LS MAR2000 (2,1,1)(0,1,1)
Waterborne A No TD; No holidays   (0,1,2)(0,1,1)
Transit A TD; No holidays AO MAY2007 (0,1,1)(0,1,1)
Aviation        
Freight M TD; Easter[2], Memorial Day, Thanksgiving_8 AO SEP2001; TC OCT2002; LS NOV2008 (0,1,2)(0,1,1)
Passenger A No TD; Easter, Thanksgiving_8 AO SEP2001; LS OCT2001 (0,1,1)(0,1,1)
Pipeline        
Natural gas M No TD; Leap year; No holidays   (0,1,2)(0,1,1)
Petroleum A No TD; Leap year; No holidays AO SEP2008 (0,1,2)(0,1,1)

NOTES:

(1) M = Multiplicative; A = Additive

(2) TD = Trading Days

(3) Moving Holidays/Calendar Effects = Easter, Memorial Day, Labor Day, Thanksgiving, and Christmas.

Easter[n] = number of days n before Easter

Easter = Thursday before to Tuesday after (6 days).

Memorial Day = Friday before to the Tuesday after (5 days).

Labor Day = Friday before to Tuesday after (5 days).

Thanksgiving_7 = Tuesday before to Sunday after (7 days)

Thanksgiving_8 = Tuesday before to Monday after (8 days).

Christmas

If Christmas falls on a Monday = Friday before through Tuesday after (12 days).

If Christmas falls on a Friday = Wednesday through Sunday after (12 days).

If Christmas falls on a Saturday = Wednesday through Sunday after (12 days).

If Christmas falls on a Sunday = Thursday through Monday after (12 days).

(4) LS = Level Shift; AO = Automatic Outlier; TC = Temporary Change