Hello David H.,
and e. g. Archibald Hurd in his book "The Merchant Navy", Vol. III, London, John Murray, Albemarle Street, W, 1929, Appendix C, has 44,692 grt of British tonnage for August 1914. But his source is quite clear - Admiralty, Statistical Review, Appendix A (and this source is compatible with Fayle's "Seaborne Trade", iii. 465, and with the abovementioned book on British ships lost).
In the book "Victory at Sea" by Admiral Sims, there are also different numbers.
Eric Grove in his book "The Defeat of the Enemy Attack on Shipping 1939-1945", Table 3, gives the following numbers: [www.gwpda.org
A complete mess.
You said Lloyds has different numbers for the British Empire.
What about smaller navies? E. g. Russian and French merchant losses in 1914?
It becomes obvious from my search (at least for 1914) that the world total losses (given by Fayle and others) are a combination of British losses by Hurd and Admiralty + some tonnage from Salter.
E. g. for August 1914 - total world tonnage lost by Fayle 62,767 grt = 44,692 grt for the British Empire (Hurd, Admiralty = merchantmen + F/V) + 18,075 grt for all the other Allied or neutral nations (apparently only merchantmen - Salter's 717 + 6,868 + 5,388 + 5,102).
(34 grt for Belgium, 40 grt for Greece from Salter not counted)...