I define SDR's as, The measure of a society's conditioning to blindly endorse the private credit of the local central bank. During the Days of Awe (Jewish) China hopped on board. When China was pledged to BRICS I offered them my $20M lien for only $50M.

Footnote 2 seems more interesting than Footnote 1 this morning. But that is because I awaken in a forgiving mood, typically. I notice on that IMF link above:

The IMF also adopted a new formula for determining currency weights in the SDR basket to address long-recognized issues with the formula that had been in place since 1978...
Stuck in traditional cause and effect by the ego always gives me the feeling that this is yet another absurd gyration I have concocted in reaction to the initial absurdity of the Bretton Woods Amendments, allowing for human flesh and bone to be traded upon as chattel. Back to my definition at the top...