Series Is Presented Here As Two Variables--(1)--Original Data, 1921-1935 (2)--Original Data, 1935-1939 Data Were Derived By Adding Freight Steam Loocomotive Miles To Departmental Miles And Multiplying The Result By Pounds Of Coal Consumed Per Engine-Mile Of Freight (Including Departmental And Shunting). Source: Computed By NBER From Ministry Of Transport Data In "Railway Statistics".
This NBER data series q03082a appears on the NBER website in Chapter 3 at http://www.nber.org/databases/macrohistory/contents/chapter03.html.
NBER Indicator: q03082a
Release: NBER Macrohistory Database
National Bureau of Economic Research, Aggregate Coal Consumption By Freight Steam Locomotives for Great Britain [Q0382AGBQ434NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/Q0382AGBQ434NNBR/, October 7, 2015.