- Various central banks publish their fitted nominal yield curve estimates: the Fed, BOE, SNB, BOC, ECB (cf: Bundesbank), RBA, Russia, RBI.
- (I couldn't find for BOJ; Brazil; BOK; or PBOC. Links for these would be extremely welcome!)
- Bloomberg has its own estimates of these zero-coupon nominal curves (e.g. USGG10YR for the US ten-year).
These estimates are not the same (at least not always), and in particular they differ in their historical availability: Bloomberg has less data. Just to pick one example, the Russian 10y on Bloomberg (GTRUB10Y Govt) has data since 2010; the central bank's website estimates back to 2003.
Does any data source have better (i.e. longer) cross-country coverage for yield curves?