I cant imagine that they have ANY meaningful data on the number of hives and or hive losses up to and before the time of internet accessibility. Getting that type of data would have taken an army of inspectors..
Even today with the internet, getting meaningful numbers seems a little difficult.. No one has come to my place asking questions. No one has gone to any beekeeper I know and asked how many hives, how many died etc.. My loss was 30% but that loss was not because of any of the mentioned problems.. I know why I lost hives, and it wont happen again. My previous losses added up to less than 6% a year, the exception being when I ordered packages.
Winter before last I lost a single hive while the CLAIM was of an average 70% loss statewide.
I think a lot of loss has more to do with management and genetics than it does any other contributing factor.
I often see claims that the heavy losses are "OK" because beekeepers can split to make up losses...
No.
Yes we can split, but that does not "MAKE UP" for losses.. those split hives are weaker, will not produce as much, and represent labor, effort and time that is un compensated. While I do not typically see the high number of losses, if they are true beyond my own area of living and life, then perhaps, concentrating on the bees a bit more than outside influences might yield better results. Just my own thoughts, based solely from personal experience..